







Un système de plusieurs équations et plusieurs inconnues 
20090122 

Cédrick pose la question : J'ai un problème écrit à résoudre estce que vous pouvez m'aider ?
Le premier est le tiers de la somme des deux autres.
La somme du premier et du deuxième est 13.
Le produit du deuxième et du troisième est 56.
Réponse: Le premier nombre est___________________
Le deuxième nombre est _________________
Le troisième nombre est _________________
PierreLouis Gagnon, Antoine Letarte at Claude Tardif lui répond. 





Combien d'éleves fréquentent cette école? 
20080404 

Jeff pose la question : Une ecole compte sept fois plus d'éleve que d'enseignants et enseignantes .De plus , le nombre de membres du personnel non enseignant correspond a la moitié du nombre d'enseignats et enseignantes . Si l'on tient compte de l'ensemble des éleves , du personnel enseignant et du personnel non enseignante , on dénombre 714 personnes . Combien d'éleves fréquentent cette école? Antoine Letarte lui répond. 





Système à deux équations 
20071211 

Fabrice pose la question : un rectangle a 130 m pour périmetre. si on diminue sa longueur de 1 m et on augmente sa largeur de 1 m, l'aire augmentera de 14m².
trouver les deux dimentions du rectangle. (on trouvera, au préalable, la difference des deux dimensions) Claude Tardif lui répond. 





Des mots aux équations 
20061102 

Julie pose la question : La diffÃ©rence de deux nombres, x et y est de 28. Le nombre y correspond aux huit neuviï¿½mes du nombre x. Trouvez ces deux nombres. Claude Tardif lui répond. 





Les equations 
19991209 

Enciso Alberto pose la question : j'ai les equations suivantes: X1=Rs + A1/(B+W^2) X2=Rs + A2/(B+W^2) X3=Rd + A3/(B+W^2) X4=Rd + A4/(B+W^2) X5=Rg + A5/(B+W^2) X6=Rg + A6/(B+W^2) dont les coefficients Ai (i=1,2,..) et B sont constants (mais on ne conais pas leur valeur) et Rs, Rd, et Rg sont inconnues. Nous pouvons constater que la dependence de ces differentes expessions en fonction de W^2 est identique. Le tracé de l'une de ces expressions en fonction d'une autre est donc une driote. . . . Claude Tardif lui répond. 





Two equations with fractions 
20201022 

mia pose la question : I am supposed to look for x and y. my teacher didn't explain very well. please help : ((
2x  y = 5
x/4 + y/3= 2 Penny Nom lui répond. 





Simultaneous equations 
20200905 

Paa pose la question : a+b=8
a+c=13
b+d=8
cd=6
find the value of each letter Penny Nom lui répond. 





A word problem involving linear equations 
20200622 

Allie pose la question : The length of a rectangular swimming pool is p m and its width is q m. Its given tht the length of the swimming pool is twice its with. if the perimeter of the swimming pool is 150 m, find the values of p and q
this is in the chapter linear equations Penny Nom lui répond. 





A system of equations. 
20200427 

solomon pose la question : xy + x =28
x + y +4 Penny Nom lui répond. 





A rectangular garde 
20200410 

Denise pose la question : In a rectangular garden a person says "if I made that bed 2 feet wider and 3 feet longer it
Would have been 64 sq,ft bigger. But if it had been 3 feet wider and two feet longer
It would have been 68 sq.ft bigger.
What is the length and width of the garden bed? Penny Nom lui répond. 





A linear system 
20200402 

Dadzie pose la question : x+s=8→1
y+x=13→2
yp=6→3
s+p=8→4 Penny Nom lui répond. 





Simultaneous equations 
20191016 

deepak pose la question : This is too complicated please help me
8/x  10/y = 1 and x+y=9 Penny Nom lui répond. 





Can one equation with two variables be solved algebraically? 
20190830 

Don pose la question : Can one equation with two variables be solved algebraically? Penny Nom lui répond. 





Two linear equations with a fraction 
20190426 

Asha pose la question : 2x=3y …1
x2+4/3(y+1) ...2
note: … is equation Harley Weston lui répond. 





Simultaneous equations with fractions 
20181214 

zaheer pose la question : solve simultaneous equations and give answer in fractional form
3x  2 = 4y +5/3
y + 7 = 2x + 4
would really appreciate some help on this please Penny Nom lui répond. 





Are those two equations the same? 
20180605 

Francisco pose la question : Solve for y: 2(x+3)=y x=5
Solve for y: (x+3)2=y x=5
Are those two equations the same? Penny Nom lui répond. 





Simultaneous equations with fractions 
20170909 

Farah pose la question : Hi, my name is Farah. I hope you can help me with this question . X/2 + g/5= 3 and 2g  f = 10 Penny Nom lui répond. 





Simultaneous equations 
20170902 

keto pose la question : xy=2,x^2+xy=12 Penny Nom lui répond. 





Simultaneous equations with fractions 
20170602 

Jamal pose la question : 1/x + 1/y =5 and 1/y  1/x =1 Penny Nom lui répond. 





Algebra 
20170528 

Kerim pose la question : I need to solve this equation.
y=at^2  2at
x =2a√t
Express y in terms of x and a
Give in the form y=(x^p/ma^3)  (x^q/na) where p,q,m and n are integers Penny Nom lui répond. 





Five equations 
20170116 

Muhammed pose la question : A x 4 = E
B ÷ 4 = E
C + 4 = E
D  4 = E
___________
& A + B + C + D = 100
what is the value of E Penny Nom lui répond. 





Simultaneous equations with fractions 
20161221 

Kimi pose la question : I am stuck on this,can someone please help me????
1/2x+1/3y=11
8x+2/5y=102
Can someone please explain how to solve questions like these??
Or else I will never learn...
Thank you Penny Nom lui répond. 





Simultaneous equations 
20161125 

Rohan pose la question : x2/3 + y  1/4 = 13/12
2x/2 + 3 + y/3 = 11/6 Penny Nom lui répond. 





Two equations 
20160917 

Nilesh pose la question : How to solve (xy)^1/2 + 3(xy) = 30 ; xy + 3(xy) = 11? Penny Nom lui répond. 





The temperature inside and outside a greenhouse 
20160722 

Mehzad pose la question : Every day, the temperature in a greenhouse is at its low temperature, 70 degrees Fahrenheit, at 2 a.m. and at its high temperature, 84 degrees Fahrenheit, at 2pm. Its temperature increases linearly between 2 am and 2pm , and decreases linearly from 2 pm and to 2am. The outside temperature follows the same linear patterns, but has a low temperature of 60 degrees Fahrenheit at 2 am and a high temperature of 78 degrees Fahrenheit at 2 pm. At which of the following times will the temperature inside and outside the greenhouse be the same?
a) 8:00 am
b) 12:00 noon
c) 4:00 pm
d) The two temperatures will never be the same Penny Nom lui répond. 





Two equations with fractions 
20160722 

kanesh pose la question : p/2+q/3=3
p/4+2q/3=3 Penny Nom lui répond. 





Simultaneous equations 
20160625 

sena pose la question : 2x/3+3y/2=1
4x5y=22
simultaneous equation Penny Nom lui répond. 





The difference between the ares of two rectangles 
20160609 

Ingrid pose la question : I am trying to help my son with an area question.
I have the answer, from the solutions, but I cannot figure out how to teach him.
Question:
Two rectangles have lengths 13cm and 19cm respectively.
Their total area is 376cm squared.
If both their widths are whole numbers, what is the difference in their areas?
I know that this is solvable once I determine the widths of the rectangles ,
but how do I go about finding that?
Thanks for your help Chris Fisher and Harley Weston lui répond. 





A pair of equations with fractions 
20160511 

tiya pose la question : hello, i want to know how to solve this question.
m/6+2n/3=6
m/10=2n/5=2 Penny Nom lui répond. 





Solve for x and y 
20160227 

ntshidi pose la question : Y=1/2x+4and1/4x6 Penny Nom lui répond. 





Two equations in two unknowns 
20160213 

Anumba pose la question : 4x + 2y = 4
7x  y = 11 Penny Nom lui répond. 





A system of linear equations 
20160124 

kareem pose la question : my name is kareem
and i am a student i have a math puzzle and i tried to solved it but it always have same mistake
xy=9
x+z=12
zn=14
y+n=2 Penny Nom lui répond. 





Two transport companies 
20160106 

Brynleigh pose la question : The Sugar Sweet Company will choose from two companies to transport its sugar
to market. The first company charges $5096 to rent trucks plus an additional fee of
$200.75 for each ton of sugar. The second company charges $5500
to rent trucks plus an additional fee of $175.50 for each ton of sugar.
For what amount of sugar do the two companies charge the same?
What is the cost when the two companies charge the same? Penny Nom lui répond. 





Constructing simultaneous linear equations 
20151228 

Deborah pose la question : Linda thinks of a twodigit number. The sum of the digits is 8. If she reverses the digits, the new number is 36 greater than her original number. What was Linda's original number?
Thank you! Penny Nom lui répond. 





Linear equations in two variables 
20151213 

priya pose la question : I have problem in solving these equations please help me today itself very urgent:
I)2x+y=y
II)pie*x+y=9 Penny Nom lui répond. 





Four equations in 3 unknowns 
20150823 

damien pose la question : solve:
S x U  T = 44
T  U x S = 36
U + T  S = 7
U x U / S = 4 Penny Nom lui répond. 





The method of elimination 
20150501 

oreanna pose la question :
Question from oreanna, a student:
How do u solve 2x+9y=3
7x4y=25 in elimination Penny Nom lui répond. 





A word problem with fractions 
20150409 

Lorraine pose la question : If the numerator of a certain fraction is doubled and the denominator is increased by 1, the fraction becomes 1/2.
If the numerator of the original faction is squared and the denominator is decreased by 2, the fraction becomes equal to 1.
Let x be the numerator and let y be the denominator of the original fraction.
Write down two simultaneous equation in x and y.
Solve these equations to find two possible values for the given fraction. Penny Nom lui répond. 





Two equations with fractions 
20150226 

Pulane pose la question : Hi math centre I've been trying to solve these equations for days now please help
(6/x)(1/y)=4
(9/x)+1=(2/y)
Please help me solve them simultaneously
Thank you Penny Nom lui répond. 





Two equations 
20150216 

nigel pose la question : 2x+1/2y=1
6x3/2y=21 Penny Nom lui répond. 





1999 equations in 1999 unknowns 
20141128 

Subrahmanya pose la question : Solve the following system of 1999 equations in 1999 unknowns :
x1+x2+x3=0, x2+x3+x4=0……., x1997+x1998+x1999=0,
x1998+x1999+x1=0, x1999+x1+x2=0.
(in x1,x2,...................,x1999 the numbers 1,2,.............,1999 are subscripts) Penny Nom lui répond. 





Two quadratic equations 
20141120 

rajesh pose la question : Sir,
I would like to discuss on question
Find the value of variable X and Y, equations are
X2+Y2+2XY=25
X2+Y22XY=1
Sir, my point is equation looks not so easy.My opinion is there many
(more than 4)value possible for both X and Y.
Kindly help me.
Waiting for your response.
regards,
rajesh Penny Nom lui répond. 





A linear system 
20141014 

pheter pose la question : 4/x  1/y = 3 .... equation (1)
6/x  2/y = 5 .... equation (2) Penny Nom lui répond. 





Two equations in x and y 
20140925 

seyilogo pose la question : solve y=2x  3 and (4x  2y) / x + y = 1 simultaneously Harley Weston lui répond. 





Two equations in two variables 
20140918 

Susan pose la question : (28x + 36y)  [20000  .75(28x + 36y) + 60000] = 5000
x + y = 10000
solving two equations involving variables Penny Nom lui répond. 





The method of elimination 
20140705 

leo pose la question : please explain how can i solve this problem
3x6y=38
6x9y=44
using elimination and simultaneous method thank you :) Penny Nom lui répond. 





Simultaneous equations 
20140620 

rana pose la question : solve the simultaneous equations
a)3x=7y
12y=5x1 Penny Nom lui répond. 





Simultaneous equations with fractions 
20140419 

Maryam pose la question : I looked at your example of simultaneous equations with fractions and applied it to my question from an educate exam papers but I couldn't get it to work. The question is:
x/8  y = 5/2
3x + y/3 = 13 Penny Nom lui répond. 





Simultaneous fractional equations 
20140215 

benjamin pose la question : hi math central. benjamin here. during class, i had problem with this topic. normally i wont have problems with math but this topic i just too hard for me. please help i am having exam and test next week on this topic
here is the question:
using substitution method, solve the simultaneous equation.
(x+1)/(y+2)=0.5
(x2)/(y1)=1/3 Penny Nom lui répond. 





Two nonlinear equations 
20140126 

Naryn pose la question : (1÷x) + (1÷y) = (7÷12)
xy = 12 Penny Nom lui répond. 





A linear equation 
20131226 

khushboo pose la question : A farmer sowed wheat and paddy in two fields of total area 5000 sq.m. Write a linear equation and draw a graph to represent the same? Penny Nom lui répond. 





Substitution type simultaneous equations 
20131103 

Kayla pose la question : I am having problems with substitution type simultaneous equations, when the variable you are substituting is a algebraic one:
y=x^23x+4 and 3x2y=1
I have rearranged 3x2y=1 to get x=(1+2y)/3 but when I substitute this x value into the other equation, I get the wrong answers!
Would appreciate any help! Thank you. Penny Nom lui répond. 





A system of equations 
20130813 

Nina pose la question : 3x2y=8
x+3y=5
What is the solution of the system of equations Penny Nom lui répond. 





Four equations 
20130808 

may pose la question : HI how to solve this 4 equations?
A+C = 0
4A+B8C+D=1
3A+16C8D=29
12A+3B+16D=5 Robert Dawson lui répond. 





Simultaneous equations 
20130710 

Warren pose la question : solve this simultaneous equation: xy=4
2x+3y=14 Penny Nom lui répond. 





4 linear equations with 3 unknowns 
20130412 

Marian pose la question : how to solve for 3 unknowns in 4 simultaneous equations Penny Nom lui répond. 





Simultaneous equations with fractions 
20130331 

Terence pose la question : 5/x6/y=1
17/x+30/y=16
I been spending whole day to solve this question. Would be very grateful if you can help I try
The denominator value is a equations term which make is simultaneous equations so hard. Penny Nom lui répond. 





f(x) + f ''''(x)=0 
20130305 

Andreea pose la question : Hei. I don’t speak lot of english but here is my question,hope u understand: f(x) + f ````(x)=0. so, my question. what is f(x), where f ````(x) is f(x) derivative by four time ? i tried to find the answer and i knew f(x) is something like that f(x)=e^x*sinx but miss something. Brennan Yaremko lui répond. 





A word problem involving toys 
20130214 

sandy pose la question : Each boy gets 5 toys.Each girl gets 3 toys.There are 150 pupils.
The boys had 74 more toys than girls.
How many boys?
How many girls? Penny Nom lui répond. 





Dropping supplies from an airplane 
20130214 

Claire pose la question : An airplane flying at an altitude of 3500 feet is dropping supplies to researchers on an island. The path of the plane is parallel to the ground at the time the supplies are released and the plane is traveling at a speed of 300 mph.
a) write the parametric equations that represent the path of the supplies
c)How long will it take for the supplies to reach the ground?
d) how far will the supplies travel horizontally before they land? Penny Nom lui répond. 





Simultaneous equations 
20130210 

Michael pose la question : 2P + 1/3V =8
3P  2/V=5 Penny Nom lui répond. 





Two quadratic equations 
20121122 

fahmie pose la question : graph and solve the intersection of the following equations:
x^2+y^2=4
x^2+2y=4 Penny Nom lui répond. 





A word problem involving a fraction 
20121012 

Derrick pose la question : If the numerator and denominator of a fraction are both decreased by 1 the fraction becomes 2/3. If the numerator and denominator are both increased by 1 the fraction will be 3/4. Find the original fraction. How to do? Penny Nom lui répond. 





2x+underroot2=3x43underroot2 
20120709 

Eshraj pose la question : 2x+underroot2=3x43underroot2 Penny Nom lui répond. 





Parametric equations 2 
20120225 

Kathy pose la question : If the angle at time 0 is not 45 degrees how can you find the initial velocity? Ball thrown from height of 7 feet. Caught by receiver at height of 4 feet after traveling 90 feet down the field. Find initial velocity. You had a similar problem answered but the angle was 45 degrees so the cos and sin were equal and the equations were simpler to work with. Thank you! Harley Weston lui répond. 





Linear equations 
20111006 

Hannah pose la question : I am confused about a question on my homework, here is an example on what I need to do:
You own a sightseeing boat tour. Kids' admission costs $5, adults' admission costs $8.
During that day you get (madeup number) $521 with 71 admissions.
How many of each passenger boarded?
I tried something like
5x + 8y = 521
x + y = 71
But, I still don't understand how to solve it! Help? Penny Nom lui répond. 





A picture with a frame 
20110819 

Aniish pose la question : A picture 8inches by 12inches is placed in a frame of uniform width. If the area of the frame equals the area of the picture find the width of the frame? Penny Nom lui répond. 





A linear equation with fractions 
20110713 

Simon pose la question : I would like to ask if you would be able to explain : linear equation: 2 1/2 (X1)  x+3 /3 = 4 , the first step shows multiplying by 2 then multiplying by 3. etc. What I don't understand is where the 2 in multiplying by 2 comes from? ( the three is pretty obvious being x+3 /3 (to get rid of the divided by) ) .
Thanks for your help. Penny Nom lui répond. 





U(n+1) = 2Un + 1 
20110522 

Cillian pose la question : In a certain sequence, to get from one term to the other you multiply by 2 and add 1, i.e. This is a difference equation of form: U(n+1) = 2Un + 1. prove that there is a maximum of 2 perfect squares in this sequence Claude Tardif lui répond. 





Eliminate y 
20110407 

Lynn pose la question : 2x + y = 8
y + 3z =5
z + 2w =1
5w + 3x = 9
Form three equations with y eliminated Penny Nom lui répond. 





Tony and his friends 
20110321 

Mieke pose la question : Using the following statements and the information given, how much money did each friend have.
Mike says, "I have $41.00 more than Tony."
Jessica says, "I have 6 times as much as Tony plus $2.00."
Ashley says, "I have 13 times the amount Tony has."
Sara says, "I have the 8 times the amount Tony has."
The total together they had was $304.00 Penny Nom lui répond. 





Simultaneous equations 
20101205 

ryan pose la question :
Question from ryan, a student:
3 4
   = 1 (1)
x y
7 2 11
   =  (2)
x y 12 Chris Fisher and Stephen La Rocque lui répond. 





What is the speed of each car? 
20101104 

Jennifer pose la question : two cars are 420 miles apart and traveling towards each other along the same road. They meet in 3.5 hours. One car is traveling 15mph slower than the other. What is the speed of each car?
This must be solved using a system of equation, I have no idea? Stephen La Rocque lui répond. 





Algebraic Equations 
20100810 

Justin pose la question : the amount of money that Mika has if she has some quarters
how fast Rya runs if she runs 5 mi/h slower than Danae
please help,
thanks, justin Robert Dawson lui répond. 





Four less than three times a number is 14 
20100416 

David pose la question : My daughter has two questions that we could use some help with.
First ?
Four less than three times a number is 14
Secound?
The quotient of 15 and w Penny Nom lui répond. 





A system of equations 
20100330 

samantha pose la question : the equations of two lines are 6xy=4 and y=4x +2.what is the value of x in the solution for this system of equations? Penny Nom lui répond. 





The sides of a 306090 triangle 
20100329 

maris pose la question : Find the sides of a 306090 triangle whose perimeter is 6. The solution must use systems of equations using 3 variables. Penny Nom lui répond. 





How many CDs and videos did the store sell? 
20100301 

dawn pose la question : A used book store started selling CDs and videos. In the first week,the store sold 40 used CDs and videos,at 4.00
per CD and 6.00 per video.The sales for both CDs and videos totaled 180.00 she wrote a system of equations to represent the situation.Then she graph the system of equations
thanks Dawn Tyler Wood lui répond. 





Substitution 
20100214 

Izayah pose la question : what is 3 ways to find the meeting point of y=2x+4 and 3x+y=7
by making 2 table and using a graph Stephen La Rocque lui répond. 





A piece of string 8 inches long is cut in two pieces 
20100202 

Susan pose la question : If you have a piece of string 8 inches long and cut it in two pieces. Then take the pieces and forms
each into a square such that the area of each squares added together equals 2. How long are the
sides of the squares?
Susan Penny Nom lui répond. 





A pair of simultaneous equations 
20100109 

Yumiko pose la question : Solve the following pair of simultaneous equations.
x^2 4x = y^24
3y=2x  3 Penny Nom lui répond. 





Solving two equations, one with a square root 
20091123 

kacie pose la question : y = square root of x+3
x4y = 7
im having trouble with this problem...i have to find where they intersect. Harley Weston lui répond. 





541.39(1 + i)^15 = 784.09 
20091014 

Fitore pose la question : Hi, I noticed that this question was already posted up, however I was hoping I could solve it without having to use logs. Can you please help me? The equation is:
541.39(1 + i)^15 = 784.09 Penny Nom lui répond. 





A right triangle 
20091012 

Josseph pose la question : A right triangle has an area of 84ft sq. and a hypotenuse 25ft long. What are the lengths of the other two sides? Penny Nom lui répond. 





Two equations in two unknowns 
20090918 

Citizen pose la question : x+3y=7
x+4y=7 Penny Nom lui répond. 





The method of substitution 
20090917 

laura pose la question : ok! i really need help with this question plz help!!
x=  4y +5
x+2y = 7 Penny Nom lui répond. 





Quadratic equations 
20090830 

jovian pose la question : how can i find the quadratic equation of the roots 2/5 and 1/3? Stephen La Rocque lui répond. 





Simultaneous equations 
20090828 

onias pose la question : solve 3/a  2/b = 1/2 , 5/a + 3/b = 29/12 Robert Dawson lui répond. 





y=2x+1 and y=2x1 
20090828 

MARICELA pose la question : Need help of how to work this problems
y=2x+1 and y=2x1
First of all what is the difference?
Second I think is easy just to work with the X y with the line in the middle
but how do you get the numbers for each side. Penny Nom lui répond. 





Linear equations 
20090823 

shwetha pose la question : The length of a rectangle is greater than the breadth by 18 cm. If both length and breadth are increased by 6 cm then area increases by 168 cm square. Find the length and breadth of the rectangle. Stephen La Rocque lui répond. 





Two equations 
20090531 

tony pose la question : y = 1.2x  32.7,
y = 0.7x + 46.15
can you please solve this for me? i am not able to figure it out... thank you
tony Penny Nom lui répond. 





Two equations 
20090518 

Bob pose la question : solve the system:
x/2  2y= 8
3x + 2/3y= 10 Stephen La Rocque lui répond. 





Stairway construction 
20090502 

Olivia pose la question : Hi, I'm Olivia and I'm in 8th grade studying algebra 1. I'm having some trouble with my math project. It has to do with rules of stairway construction. It says that there are two generally accepted rules to building stairs.
Rule 1: x+y=43 and x+y=46 (cm)
Rule 2: 2y+x=61 and 2y+x=64 (y is the riser and x is the tread length)
I cant figure out how to graph them...it says they're supposed to intersect to make a square which is like the safety zone for building stairs (the stairs' rise and tread lengths are plotted as points) any points outside of that square are considered unsafe.
Did i explain it ok? Thanks for your help.
olivia Penny Nom lui répond. 





Negative nine minus 7x = negative 5 
20090423 

gigi pose la question : what is negative nine minus 7x = negative 5 Robert Dawson lui répond. 





An infinite number of solutions 
20090324 

Sean pose la question : this is a linear equations problem;
first:
3535.5 + Fbd (.866) + Fbc (.5)  Fab (.5) = 0
and
3535.5  Fab (.866)  Fbc (.5)  Fbd (.5) = 0 Harley Weston lui répond. 





The substitution method 
20090218 

Nicolette pose la question : I am working on linear programming problems that I need to solve pairs of linear equations for. I am confused and am not sure how to solve these problems!
5x+3y=7 y=x3 How can i solve this using the substitution method? Penny Nom lui répond. 





A rectangular park 
20090206 

Debbie pose la question : A park named Writer's Rectangle opened in town. When asked about the dimensions of the rectangle, the city planner, responded with these clues: The diagonals of the rectangular park plus its longer sides together measure seven times one of the shorter sides. The length of one diagonal is 250 m longer than one of the shorter sides. Use this information to find the area of the park. Stephen La Rocque lui répond. 





The substitution method 
20090206 

amber pose la question : Pleasse help me with this problem
x+y=2
y2x=1 Penny Nom lui répond. 





Simultaneous equations with an xy term 
20090201 

angelee pose la question : xy+5x2y10=0
2x+y=1 Penny Nom lui répond. 





Sheep, goats, and hogs 
20090123 

La pose la question : A man buys sheep, goats, and hogs, to the number of 100, for 100 crowns; the sheep cost him 1/2 a crown apiece; the goats cost him 11/3 crowns apiece; and the hogs cost him 31/2 crowns apiece. How many had he of each? Robert Dawson lui répond. 





System of equations  comparison method 
20090102 

nick pose la question : Hi, I am doing a project on system of equations by using comparison method,
but for some reason or another, i can't seem to find any information on the
comparison method at all. So, please would you help me by giving me a website
that you know of that has some information on my method. And, if you know the
answer, can you please tell me why or when do we use system of equations by
using comparison method?
Thank You Robert Dawson lui répond. 





Quadratic equations arising from practical problems 
20081124 

Lenval pose la question : Why do quadratic equations arising from practical problems often give physically impossible solutions such as negative distances, negative times or, say, a polygon with a negative number of sides? For example: "A river in flood carries a tree tsquared  23t metres downstream in t seconds. How long does it take for the tree to be carried 50 metres downstream?" This gives t=25 and t=2. Please explain the second 'solution', which is not physically possible. Chris Fisher and Victoria West lui répond. 





Separating variables 
20081104 

Terry pose la question : by separating variables solve the initial value problem
(x+1)y' + y = 0 y(0) = 1 Harley Weston lui répond. 





A linear system 
20081022 

Tiffany pose la question : solve:
x + y + z = 4
2x  3y  z = 1
4x + y  2z = 16 Penny Nom lui répond. 





Two equations in two unknowns 
20081017 

Dushayne pose la question : Please help me in solving this problem:
a. 3x4y=32
5x+2y=10
b. 2x+3y=11
4x+3y=10 Penny Nom lui répond. 





Two equations in two unknowns 
20080801 

James pose la question : Question from james, a student:
3x+2y=9;24x2y=18
My math teacher says that it is (2,4)
Can someone please explain how to figure this out by graphing? Victoria West lui répond. 





Simultaneous equations 
20080723 

Franco pose la question : Solve
3 D + E  F = 10
2 D  F = 4
3 D  4 E  F = 25
Franco Penny Nom lui répond. 





solving four simultaneous equations 
20080718 

Muhammad pose la question : 2B2C+4E=1
A+B+C+D=0
2B2C2D+E=0
B+C+4D2E=0 Janice Cotcher lui répond. 





3y^2  48 = 0 
20080623 

marquis pose la question : 3y^2  48 = 0 Stephen La Rocque lui répond. 





Cows and chickens 
20080616 

damebochie pose la question : I got this problem and want to write a system of equation for it:
Farmer Joe has cows and chickens on his farm. One day he count 76 legs and 24 heads. How many cows and how many chickens are on the farm? write a system of equations and solve.
I don't have any problem to solve it, but I just can;t see how I am going to write this system of equation.
Thank you so much for helping? Harley Weston lui répond. 





Substitution method 
20080530 

taquicia pose la question : 2yx=3
x=5+y Janice Cotcher lui répond. 





Polar coordinates 
20080305 

kumi pose la question : 2.Sketch the graph of r=(2)/(1sinθ). Make sure you show a complete chart demonstrating how you arrive at your sketch, and sketch the graph neatly and clearly with proper labeling.
b. change the equation above to cartesian coordinates and identify the type of graph.
c.explain which coordinate system gives an easier function to graph and why
d.find a function of the form r=f(θ) for a circle centered at (8,π/2) and with the point (0,0) lying on the circle Penny Nom lui répond. 





Parametric equations 
20080305 

kumi pose la question : I have made a picture of a football pass 45 degrees with 30yds and height of 7ft and 4ft. But I am just stuck there. I have stared at the worksheet for soo long. I have no idea how to solve this, and I don't even know where this is going (I don't understand how parametric equations work). Can you help me with this problem?
1.The quarterback of a football team releases a pass at a height, h, of 7ft above the playing field, and the football is caught by a reciever at a height of 4ft, 30yds directly downfield. The pass is released at an angle of 45 degrees with the horizontal with an initial velocity of vo. The parametric equations for the position of the football at time t are given, in general, by x(t)=(vo cosθ)t and y=h+(vo sinθ)t16t^2.
a. find the initial velocity of the football when it is released
b. write the specific set of parametric equations for the path of the football
c.use a graphing calculator to graph the path of the football and approximate its maximum height
d. find the time the reciever has to position himself after the quarterback releases the football Harley Weston lui répond. 





Simultaneous equations 
20080229 

CONOR pose la question : I was wondering if you could help me with this problem
7x  5y = 1
3y = 4x Penny Nom lui répond. 





Two job offers 
20080210 

Kelly pose la question : Raja has been offered two jobs.
Each of these jobs takes 24 weeks to complete.
One job pays $3440 every 8 weeks. The other job pays $2700 every 6 weeks.
Raja wants to accept the job that pays more per week.
Show how to use equations to help Raja make her choice. Penny Nom lui répond. 





Two equations in x and y 
20080201 

leslie pose la question : 6x+8y=40 4x+5y=25 Penny Nom lui répond. 





18/95 x t =3 3/5 
20080128 

emily pose la question : 18/95 x t =3 3/5 Penny Nom lui répond. 





x=sint, y=cos2t 
20080114 

Art pose la question : How do i transform x=sint y=cos2t into a function in terms of x and y Harley Weston lui répond. 





System of equations 
20071206 

Jenn pose la question : change the equation,xy=4 to form y=mx+b
the solution to the system of equations y=2x and y=x+3 is Stephen La Rocque lui répond. 





Chicken and goat feet 
20071205 

Kim pose la question : Old McDonald raises goats and chickens. The animals have a total of
100 heads adn 360 feet. How many goats and how many chickens does Mr.
McDonald have? Stephen La Rocque and Penny Nom lui répond. 





A particle moves in the xyplane 
20071112 

Russell pose la question : A particle moves in the xyplane with
X = 2t^3  12t^2 + 18t
Y = 3t^4  28t^3 + 72t^2
find an equation of the line tangent to the given curve at t_0_ = 1
note: t_0_ is t subscript 0 Harley Weston lui répond. 





a/5= b/7= 8/3 
20071027 

Kristine pose la question : how do you solve for a and b in this equation:
a/5= b/7= 8/3 Penny Nom lui répond. 





4x+8y=32 
20071018 

Sara pose la question : Rewrite the following equation:
4x+8y=32
in function form ("solve for y"). Penny Nom lui répond. 





Four triangles in a square 
20071015 

Kristina pose la question : A square with side lengths of 6 cm is divided into 3 right triangles and a larger isosceles triangle. If the three right triangles have equal area, find the exact area of the isosceles triangle. Stephen La Rocque lui répond. 





Substitution method 
20071011 

Kevin pose la question : 3xx+2y=36y=11 Stephen La Rocque lui répond. 





Coin jar 
20071007 

a student pose la question : Sally empties his jar of coins. It contains $3.75 in nickels, dimes, and
quarters. The number of dimes is twice the number of nickels and the number
of quarters is three less than the number of nickels. Determine how many nickels,
dimes, and quarters were in the in the jar. Stephen La Rocque lui répond. 





Solving four simultaneous equations (system of four linear equations) 
20071007 

Johan pose la question : I need some help in solving this question
x + 2y  3z + 4w = 12
2x + 2y  2z + 3w = 10
0 + y + z + 0 = 1
x  y + z  2w = 4 Stephen La Rocque lui répond. 





Problems solved using quadratic equations 
20071007 

Lisa pose la question : a. Two positive numbers differ by 5. Their product is 234. What are the two numbers?
b. The sum of two numbers is 12. Their product is 30. What are the two numbers?
c.Two numbers differ by 5. Their squares differ by 55. What are the two numbers?
d. The sum of two numbers is 15. Their product is 56. By forming an equation, find the two numbers. Penny Nom lui répond. 





Finding equations, intersection point of two lines at right angles 
20070922 

Yaz pose la question : Find the equation of the line joining A(1,9) to B(6,120). Another line passes through C(7,5) and meets AB at rigth angle of D. Find the euation of CD and calculate the coordinates of D. Stephen La Rocque lui répond. 





Two equations in two unknowns 
20070914 

CAMEILA pose la question : NEED T0 SOLVE THIS EQUATION
Y = 2X + 6
Y + 6 = 2x Stephen La Rocque lui répond. 





Parametric equations 
20070822 

will pose la question : Graph and make a sketch of x = ysquared  6y + 11 in parametric mode (hint: you need to come up with 2 parametric equations).
i have already figured out that the cartesian form of the parametrics will be y = +/ sqroot(x2) + 3, but i do not know how to produce 2 parametric equations from this. Penny Nom lui répond. 





What feature on a graph shows the solution? 
20070819 

San pose la question : To solve the equation 2sinx+square root 3=0, what feature of the graph,
in the form y=asinx+b would show the solution? Draw a graph to show
the solution. thanks. Stephen La Rocque lui répond. 





Finding the radius of an inscribed circle 
20070705 

Maria pose la question : I need to find the radius of a circle which is inscribed inside an obtuse triangle ABC. I know all the angles and all the lengths of the triangle. Stephen La Rocque and Chris Fisher lui répond. 





Simultaneous equations : the Elimination method 
20070621 

Patricia pose la question : I need to find the value of X and Y using the Elimination method.
5/x + 3/y=4
25/x2/y=3 Stephen La Rocque lui répond. 





Angles of depression 
20070613 

Phonda pose la question : The pilot of a small private plane can look forward and see the control tower for a small airstrip. Beyond that is a large factory that is 3 milies from the airstrip. The angles of depression are 12.5 degrees and 4.8 degrees respectively.
Find the airplane's altitude, to the nearest ten feet. Stephen La Rocque lui répond. 





What happens when you have zero's on both sides? 
20070605 

Lily pose la question : On the substitution method what happens when you have zero's on both
sides of the equation? Is that considered no solution or infinitely many? Stephen La Rocque and Penny Nom lui répond. 





System of equations 
20070524 

Chris pose la question : Find all real solutions (x,y,z,w) of the system of equations:
2y= x + x/17, 2z= y + y/17, 2w = z + z/17, 2x= w + w/17 Penny Nom lui répond. 





Set up two simultaneous equations 
20070521 

Admire pose la question : The cost of producing windscreen wipers blades at a factory ais partly fixed (due to operating overheads) and partly dependent on the number of blades produced. It costs $300 to produce 1000, and $600 to produce 5000 blades. How much would it cost to produce 24000 blades? Penny Nom lui répond. 





A tugboat's speed 
20070430 

Amanda pose la question : a tugboat must travel 24 miles against a 4 mile per hour current on the Potomac River and return. At what
constant speed must the tugboat travel to make the trip in 12 hours. Round answer to the nearest tenth mph. Stephen La Rocque lui répond. 





Two equations 
20070429 

lavon pose la question : I'm having trouble figuring out a linear equation, can you help?
 3x + 2y = 8
3x + 2y = 8 Penny Nom lui répond. 





Simultaneous equations 
20070416 

kyrie pose la question : simultaneous equation
4x + 3y = 21
2x * y = 8 Penny Nom lui répond. 





Solve for x and y 
20070327 

anthony pose la question : solve y=4x and x+y=5 Sara Ulmer lui répond. 





Simultaneous equations with fractions 
20070228 

Alyca pose la question : Hello Math Central, I am a grade 10 student taking Academic math. Our unit right now is method of substitution and elimination. I'm stuck on this one question that I've been doing forever. Please help =)
*For this equation I have to do method of elimination, but it's so much harder with fractions...could some one please explain to me how to do it step by step?* x y 2    =   3 6 3 x y 1    = 1 12 4 2
Steve La Rocque and Ashley Mang lui répond. 





Simultaneous equations with envelopes 
20070208 

Mick pose la question : There were 17 envelopes bought, some were brown, some were white. The brown envelopes cost one cent more per envelope than the white ones. The total cost was 80 cents. How much of each type of envelope was bought? Many thanks! Stephen La Rocque lui répond. 





Dividing money unequally 
20070206 

Linda pose la question : I have a total of $13,826.48. It is to be divided by 15 kids  2 of the kids only get half of what the other 13 do  how much do the 13 get and how much does the 2 get? Thanks Haley Ess and Steve La Rocque lui répond. 





Equations with fractions 
20070206 

Juan and Derek pose la question : 3/4x=1/2 3/4+1/5x+1/3=4/5x Penny Nom lui répond. 





Nickels, dimes and quarters 
20070205 

Avinash pose la question : Mary has 48 coins made up of nickels, dimes and quarters with a total value of $5.10. She has 4 more dimes than nickels and quarters combined. How many coins of each kind does she have? Use matrix to solve the system Stephen La Rocque lui répond. 





Fencing a field 
20070201 

Carol pose la question : "The area of a rectangular field is 1200m^2. Two parallel sides are fenced with aluminum at $20/m. The remaining two sides are fenced with steel at $10/m. The total cost of the fencing is $2200." What is the length of each side fenced with aluminum and steel? Stephen La Rocque lui répond. 





The substitution method 
20070131 

Victoria pose la question : how do i solve this problem using the substitution method? 2x5= 14 7x+14y= 5 Stephen La Rocque lui répond. 





The elimination method 
20070131 

Addrianna pose la question : x2y=2 3x5y=7 Stephen La Rocque lui répond. 





A boat travels 60 miles downstream in the same time it takes to go 36 miles upstream 
20070127 

Liz pose la question : A boat travels 60 miles downstream in the same time it takes to go 36 miles upstream. The speed of the boat in still water is 15 mi/h greater than the speed of the current. Find the speed of the current. Stephen La Rocque lui répond. 





The sum of the digits of a twodigit number is 13. 
20070127 

Liz pose la question : The sum of the digits of a twodigit number is 13. If the digits are reversed, the new number is 9 more than the original number. Find the original number. Penny Nom lui répond. 





An algebra exercise 
20070124 

Clara pose la question : Given x + 2y = 2 and x  2y = 18, find: a) x^2  4y^2 b) x^2 + 4y^2 Stephen La Rocque and Penny Nom lui répond. 





Points of intersection 
20070118 

Mark pose la question : Find the points of intersection of the given pair of curves. 2x  3y = 8 and 3x  5y = 13 Steve La Rocque and Haley Ess lui répond. 





A system of equations 
20061113 

Katrina pose la question : solve the system of equations using either the substitution or the elimination method. 2x3y= 12 and 4x+6y=15 Penny Nom lui répond. 





(4x5)^2 = 32 
20061111 

Tracey pose la question : (4x5)^2 = 32 Stephen La Rocque and Penny Nom lui répond. 





Simultaneous equations 
20061106 

An other pose la question : e^2yx+2=0 ln(x+3)2y1=0 Penny Nom lui répond. 





Balancing equations 
20061026 

Della pose la question :
With the following equations, how do you know whether you need to apply the multiplication or division rule of equality? 75% t = 18 120% w = 72 Penny Nom lui répond. 





Word equations 
20061022 

Samira pose la question : One half of a number is subtracted from the sum of onethird and onequarter of the same number. If the result is 16, find the number. Stephen La Rocque lui répond. 





How much did I spend on the first trip? 
20060910 

Alexander pose la question : I have $600 to spend.
I take 10 shopping trips.
Each trip I spend $10 more than the last trip.
How much did I spend on the first trip?
Stephen La Rocque lui répond. 





Making and using equations 
20060830 

Brooke pose la question :
write an equation to model the relationship between these variables. Define the variables you use, and refer to your notes for a variety of formats of equations we have studied this year.
week 1: 3 birds infected
week 2: 15 birds infected
week 3: 75 birds infected
week 4: 375 birds infected
Stephen La Rocque lui répond. 





If 5x + 4y = 6 then x + y = ? 
20060818 

Vijai pose la question : If 5x+4y=6
then x+y=? Stephen La Rocque and Penny Nom lui répond. 





I want to calibrate a glucose meter 
20060727 

John pose la question : If I have 3 glucose control solutions having:
Low  50 mg/dl
Normal  100 mg/dl
High  330 mg/dl
I want to calibrate a glucose meter but I need more than these 3 data points. How can I mix these up to get different concentrations in between 50 and 100, 100 and 330. I would like to mix up different concentrations and put them in test tubes or whatever to do some calibration work. Like 70 mg/dl, 90 mg/dl, etc. More data points should be in between say 50 and 100 since this is normal, 90 mg/dl is considered close to normal.
Stephen La Rocque lui répond. 





Three people go to a store where there is a sale 
20060530 

Geocee pose la question : Three people go to a store where there is a sale. One person buys two shirts, one pair of pants and one sweater. The second person buys one shirt, two pairs of pants and two sweaters. The third person buys three shirts and four pairs of pants. Find the price of each item if the first person spent $155 and the second and third person spent $235 each. Stephen La Rocque lui répond. 





Simultaneous Equations 
20060524 

Angie pose la question :
Question: solve the equations
2x3yz=0
3x2y+z=5
x+3y2z=14
for x,y,z
Stephen La Rocque lui répond. 





x7=20 and 2x+5=17 
20060404 

Janette pose la question : I'm trying to help out my daughter, it has been much too long since I've been in school. The question is x7=20 and the other question is 2x+5=17. What are the formulas? Penny Nom lui répond. 





2x+5y=3 And x+3y=7 
20060403 

Lloyd pose la question : simplify 2x+5y=3 And x+3y=7
Penny Nom lui répond. 





2x+3y=0 and 3xy=0 
20060314 

Lisa pose la question : my name is lisa I am doing math for work and i have a math problem to solve and i need help with it here is the question 2x+3y=0 and 3xy=0 this is one question can you help me please Penny Nom lui répond. 





One boundary of a pond is parabolic in shape. 
20060120 

Glenn pose la question : One boundary of a pond is parabolic in shape. The boundary passes through the points A(20,45), B(40,40) and E(30,35). The equation of the parabola is of the form y=ax2+bx+c. Find the equation of the parabola and the coordinates of the vertex of the parabola. Any assistance you could provide would be greatly appreciated. Penny Nom lui répond. 





Simultaneous Equations 
20051221 

Matt pose la question : I have these two equations,
336 = 60a + 10b
and
432 = 84a + 6b
Am I right in saying both a and b are 4.8? Penny Nom lui répond. 





5(x3)/4 =x+1 
20051214 

Jennifer pose la question :
I have two problems i am stumped on I don't know how to help my daughter.
5(x3)/4 =x+1
3(x+12)/5 =x +2
Penny Nom lui répond. 





An integer equation 
20051201 

Henry pose la question : 3x = 2y + 7
I know the answer: x=9 and y=10, but what are the algebraic steps to solve the equation? Penny Nom lui répond. 





Graphing two lines 
20051120 

A student pose la question : About y = 5x + 24 and y = 3x  8
1. Graph both equations on the same set of axes. When you made your graph, how did you choose the range of x and y values?
2.Find the point of intersection for the graphs.
3. Test the point of intersection you found by substituting its coordinates into the equations. Do the coordinates fit the equations exactly? Penny Nom lui répond. 





Solving a pair of equations 
20051110 

Steven pose la question : what is answer to
2 x + y = 1
y = ^{1}/_{3} x  4 Penny Nom lui répond. 





3x  5  (4x  8) = 2(2  3x) + 29 
20051106 

Emma pose la question : I do not get how to "solve for x". For example:
3x  5  (4x  8) = 2(2  3x) + 29 Penny Nom lui répond. 





Simultaneous equations 
20051013 

Daniel pose la question : 5x + 3y = 22
4x  7y = 20 Penny Nom lui répond. 





6x+7=8x13 
20050927 

A student pose la question : show me how to do 6x+7=8x13 Penny Nom lui répond. 





14p  8 = 22 + 20p 
20050927 

Tiffany pose la question : 14p  8 = 22 + 20p Penny Nom lui répond. 





A system of equations 
20050902 

Gina pose la question : How do you interpret the solution of a system of equations by the corresponding graph? Demonstrate your answer by the use of an example. Penny Nom lui répond. 





Discriminant 
20050620 

A student pose la question : If a quadratic has real root, its discriminant b24ac>=0 Is there any similar condition or method by which you can find whether roots of a cubic equation are real or not? Chris Fisher lui répond. 





y = x+2 and y = 2x  1 
20050503 

Kimberley pose la question : Question:
y=x+2
y=2x1 Penny Nom lui répond. 





2^10 = 1/2^x  1 
20041213 

Randy pose la question : Could you explain to me how the following equation is solved please.
2^10 = 1/2^x  1 Harley Weston lui répond. 





The substitution method 
20041128 

A student pose la question : I Was working and i ran into this problem can you help me solve it using the substitution method?
3x2y=10
x+5y=27 Penny Nom lui répond. 





Solve for a and t 
20041023 

Justin pose la question : How do I solve for "a" and "t" in the equations:
1000t= 4000 + 2000t + (1/2)at^2
1000=2000 + at Penny Nom lui répond. 





The integrating factor method 
20040805 

A student pose la question : Whilst using the integrating factor method, I am required to integrate a function multipled by another function.
say f(t) = exp(kt) and some other function g(t); where exp = exponential and k is some constant.
Integral f(t)*g(t) dt or
Integral exp(kt)*g(t) dt
What would the result of this integral be? I have never met an integral like this before. Would it simply be exp(kt)*g(t)/k?
More specifically, the problem and my attempted answer is in PDF format:
In my attempted solution, I am unsure about the last two lines I have written out, as it relates to integrating a function multipled by another function. Harley Weston lui répond. 





Solving some quadratic equations 
20040715 

A student pose la question : Could you please solve the following for x
x^{2}+6=5x
x^{2}+16=8x
2x+21=3x^{2} Penny Nom lui répond. 





Setting up an equation 
20040430 

Matt pose la question : I am trying to determine the dimensions of a 22 megapixel digital camera chip that has a 3:2 ratio. We know then, that: 3x = 2y (or 1.5x = y)
and that
xy = 22
Beyond this, I don't know how to hook those 2 seemingly unrelated facts together. Penny Nom lui répond. 





The substitution method 
20040214 

Keisha pose la question : I need to solve this problem by using the substitution method.
3x+y=1
x=2y+5
Please help me understand the method to solve. Penny Nom lui répond. 





Diamonds and Pearls 
20031211 

Lauren pose la question : A crown holds a total of 3080 jewels.
It is made up of diamonds and pearls.
There are 10 times as many diamonds as there are pearls.
How many pearls are there? Penny Nom lui répond. 





Mr.Carter is very cautious 
20031126 

Bob pose la question : Mr.Carter is very cautious. He decides to invest in only three stocks: one low stock, one high stock, one medium stock. Given that the expected annual yields are 6% for low stock, 7% for medium stock, and 8% for high stock, he wants his investment in medium stock to be half of his total investment in low and high stock. How much should I invest in each type fo stocks to expect a total annual return fo $650 form my investments? Harley Weston lui répond. 





Systems of equations 
20031119 

Scott pose la question : I hope that u can help me....I
am a college student taking a class in Pre Calculus.....I have homework
due this Friday and it counts a BIG Percentage on my FINAL grade.....I
am getting mixed up and can not figure out a few problems.....Please help
me.....
Method Of Subsitution
Problem 1. y 8x = 5
x(squared) + y(squared) = 25
Problem 2. y = x(squared)  2x  6
Y = x(squared)  4
Penny Nom lui répond. 





The product of the page numbers 
20031107 

Morgan and Mom pose la question : You open a book and the product of the page numbers is 12,656. What are your page numbers? Penny Nom lui répond. 





Solve for x 
20031027 

Lonnie pose la question : i need help with solving equations and formulas such as 3x+b=6x, for x. I do not understand how you find x. Penny Nom lui répond. 





Substitution method 
20030914 

John pose la question :
Hello, my name is john and while I was finishing up my work I stumbled into these problems. a/4b=1 a+b=11 and 6ab=5 4a3b=8 Thanks a lot. I really need some help :) John Penny Nom lui répond. 





Two equations 
20030821 

Jennifer pose la question :
The following problems have me stuck and any help would be greatly appreciated seeing my text book is doing me no favours:
3^{2a+1}  283^{a} + 9=0 and 5^{2m}  5^{m}=20 Penny Nom lui répond. 





x+3 = 15x 
20030719 

Nathan pose la question : Without the use of trial and error, is there a way of solving for x where x + 3 = 15x? I know that x = 0.1875, but how do I find whether x + 3 is positive or not if I did not have this information (In other words, how would I solve whether the xvalue was 3 or less, or if it was more than 3)? Claude Tardif and Penny Nom lui répond. 





Setting up a word problem 
20030630 

Christie pose la question : A rectangular corral is forty feet longer than it is wide. If the perimeter is 220 feet, determine the length and width of the corral. Penny Nom lui répond. 





Sesame Street on Stage 
20030625 

Christie pose la question : Sesame Street on Stage has different ticket prices for adults and for children under 6. Beth and her two children, ages 3 and 4, paid $15 to gain entrance, while Jamie and John Jacobs and their 2year old daughter got in for $19.50. What is the ticket price for adults? Penny Nom lui répond. 





The substitution method 
20030414 

Patty pose la question :
I need help with the following: 5x  4y = 13 2y + 3x = 1 Penny Nom lui répond. 





(n+17)(n+7) = 0 
20030305 

Janea pose la question :
What is the answer to 1. (n+17)(n+7)=0 What is the answer to:2. (y15)(y100)=0 Penny Nom lui répond. 





Two equations in two unknowns 
20030206 

Patrick pose la question : What are all ordered pairs of real numbers (x, y) for which: y^{x2  7x + 12} = 1 and x + y = 6? Penny Nom lui répond. 





Quadratic equations 
20021210 

Katie pose la question : just bugging the hell outta me and I cannot figure it out for the life of me.
1)x2x1 =0 Find both roots. You must simplify both of your roots. This equation requires the use of the Quadratic Formula. I have tried everything for this and I am still either getting the wrong answers, and end up getting really frustrated. If you could find the answers and tell me how you did it I would greatly appreciate it! Then the second problem is
2) The square of a certain negative number is equal to 70 decreased by 3 times the number. Find the answer! On this one I set it up but still came out with the wrong answer. So if you could help me on this one I would greatly appreciate it! Penny Nom lui répond. 





The substitution method 
20021115 

A student pose la question : Solve by using the substitution method. x = 3y  1 x + 2y = 9 Penny Nom lui répond. 





Determining a parabola 
20021106 

Shelley pose la question : let (0,3) and (1,9)and (1,1) be given points in a parablola. Determine a b and c Penny Nom lui répond. 





How many trees were planted in March? 
20021020 

Allison pose la question : The number of trees planted by the Alpine Nursery in April was 3 more than twice the number of trees planted in March. If 71 trees were planted in april, write and solve an equation to find how many trees were planted in March. Penny Nom lui répond. 





Solving an equation 
20020922 

Emanuel pose la question : how do u solve these problems?:
30/x=7+ 18/2x
3m+1/4 = 2 32m/3 Penny Nom lui répond. 





Formulating equtions 
20020914 

Theresa pose la question : Hello. In math class we have to formulate equations for certin questions for extra credit. We are allowed to ask anyone and anyone can do it for us and explain it to us. Could you please do that? Here are the questions  Jordan has 3 times as much money as Reva. Together they have $44. How much money does each have?
 The Tigers played 48 games. They won twice as many as they lost. How many did they win?
 There are 900 students in Sewickley Academy. There are 20 more girls than boys. How many girls are there?
 A board 400 cm long is cut into 2 pieces. One piece is 66 cm longer than the other. Find the lenght of the shorter piece.
Penny Nom lui répond. 





A solution to an equation 
20020828 

A student pose la question : How do you determine whether a pair of numbers is a solution for an equation? If you could identify the specifics steps I need to take to determine whether it is a solution or not would be appreciated! Thanks i.e. x4=0 Pairs of numbers as possible solutions (4,7) (3,4) (0,4). Penny Nom lui répond. 





Express 5120 as a sum of consecutive numbers 
20020825 

Todd pose la question : Express 5120 as a sum of more than 1 consecutive number. Leeanne Boehm lui répond. 





Two equations 
20020726 

Derek pose la question : 1. 3x + 2y = 4 2. 7x + 2y = 24 finding x and y. Penny Nom lui répond. 





25m = 100 
20020422 

Megan pose la question : If 25m = 100, Then m equals what number? Penny Nom lui répond. 





An augmented matrix 
20020420 

A student pose la question : Hi my math teacher asked us to solve an augmented matrix. I am in twelfth grade and need help. The book we are working on is college algebra. Here it is a+2b+c=0 2a+5b+4c=1 ab9c=5 Penny Nom lui répond. 





Pairs of equations 
20020404 

A student pose la question :
high school level student is asking
y=4x x=4y
x+y=5 3x+2y=20
y=x1 3xy=4
x+y=3 2x3y=9
x+5y=4
3x+15y=1
. . .
Penny Nom lui répond. 





The substitution method 
20020224 

Joe pose la question : whats the answer to this question? 3x+y=11 x+2y=3 its substitution method i am having alot of trouble figuring it out. send the answer as soon as possible. thank you Penny Nom lui répond. 





Algebra review questions 
20020114 

A student pose la question :
 A wildebeast was observed racing a distance of 86.4m in 4.8 seconds. Find the speed of the wildebeast in m/s.
 8x  7  5x = 23
 7 z  3 (z + 2) = 26
Penny Nom lui répond. 





Simultaneous equations 
20011217 

Matthew pose la question : 4x + y = 4 2x  3y = 5 what is x and y Penny Nom lui répond. 





A rightangled triangle 
20011213 

Pamela, Jeff, Kayleigh and Jacob pose la question : A rightangled triangle has one side that is 8 cm shorter that the hypotenuse. The other side is 1 cm shorter than the hypotenuse. Find the length of the sides. Penny nom lui répond. 





Two equations in two unknowns 
20011204 

Courtney pose la question : y = 3x + 2 y = 4x  5
solve for x Penny Nom lui répond. 





Undetermined coefficients 
20011122 

Hoda pose la question : The equation is: y"  2y' + y = t e^{t} + 4 We need to use The method of Undetermined coefficients. I have tried assuming that the solution is Ate^{t}+Be^{t}+C, but all I get is C=4 and I tried (At^{2}+Bt+C)e^{t}+D, but again I get 0=0 when I calculate the first and second derivatives, so i get no information on the constants. Any suggestions? Harley Weston lui répond. 





Investing in a yacht 
20010926 

Junior pose la question : Marvin and his four friends wish to invest in a yacht by sharing equally in the cost. As the date of sale approaches, Marvin realizes that if three more people join the partnership, each partner's share would decrease by $18,000. How much does the yacht cost? Penny Nom lui répond. 





Solving trig equations 
20010922 

Asad pose la question : Can you please explain to me how to solve trig Equations,e.g sin(x)=x^{4}+12/2+cos(x)=x^{6}+9/3= (if this can be solved) Claude Tardif lui répond. 





Matrix reconstruction 
20010719 

Guy pose la question : Is there a way to get the sums of rows, columns and diagonals of an n x n matrix to reconstruct the original matrix? Walter Whiteley and Patrick Maidorn lui répond. 





Common solution 
20010602 

Samantha pose la question :
 Solve for common solution: x+y=6 2x3y=2
 Solve for y in terms of x: 3xy=4
Penny Nom lui répond. 





Graphing equations 
20010501 

A student pose la question : If, for example, 4x^{2}12x+9=0 and 4x^{2}+12x9=0, which I'm assuming it does since you can derive that equation from the first, why do those two equations have different graphs? Penny Nom lui répond. 





Solving some equations 
20010416 

Justin pose la question : Solve the following equations for x  x+7=10
x=
 x7=10
x=
 3x=7
x=
 x/3=10
x=
 .
 .
 .
 .
Penny Nom lui répond. 





Where do the lines y=2x4 and y=x1 intesect? 
20010406 

Bryce pose la question : solve the following problem by setting them equal to each other. Solve for x and y. Where do the lines y=2x4 and y=x1 intesect? Penny Nom lui répond. 





Systems of equations 
20010316 

joy pose la question : How do u solve problems using systems of equations? ~ finding x and y~ ex:
26 = 3x  2y 42 = 4x + y Penny Nom lui répond. 





Quadratic equations 
20010311 

Philip pose la question : I am a student in the UK and i am in secondary school and i am doing my GCSE next year. here are my questions: solve the following equations correct to 2 decimal each time. [1] 2xsquared + 5x = 1 [2] 3xsquared(2x+1)=1 [3] xsquared + 7x + 2 = 2x + 4 [4] 5xsquared  3x = xsquared + 4 Penny Nom lui répond. 





The substitution method 
20010305 

A student pose la question : Solve each system of equations by the substitution method. Show your work.  y = 8
7x = 1  y
 y = x  1
4x  y = 19 Penny Nom lui répond. 





Solve for the variable 
20010228 

Ashley pose la question : I've got 2 questions. We (my dad and I) can not figure them out. please help me.  21 = 9  2 (4a + 2) and I am supposed to find out what the variable is.
 2/3 n + 3/8 n = 15/16 (those are fractions). Again, I need to find out what the variable is.
Penny Nom lui répond. 





Solving Equations 
20010223 

Stephanie pose la question : Do you know who came up with solving equations? Do you have any websites that can give me good information on solving equations? Do you know any history on solving equations? Do you know what solving equations is used for? And finally............Sorry about all of the questions :) Has the form of solving equations changed from the time it came out to now? Juci McDonald lui répond. 





Linear equations 
20010213 

Jamie pose la question : I have a question how do you do linear equation? Penny Nom lui répond. 





Blood flow and age 
20010111 

Gayle pose la question : I don't understand the second part of this problem Here is the first part that was correct. A 35yr old has 100% blood flow. A 65yr old has 64% blood flow. Find the rate of change per yr in the percent of blood flow. (This part is correct) m=(64100)/(3565)= 36/30= 1.2 per year of blood flow. Now, here is the second part I DON'T UNDERSTAND! .Let b represent the percent of blood flow and a represent a person's age. Write an equation that you could use to predict the percent of blood flow for a person of any age over 35. Penny Nom lui répond. 





x^5 + y^5 + z^5 = w^5 
20010111 

Samuel Brown pose la question : x^{5} + y^{5} + z^{5} = w^{5} I have no idea whether or not this is possible. Claude Tardif lui répond. 





A piecewise linear equation 
20001124 

Jacky pose la question : There is a light bulb and it is given that the light bulb cost $0.75 and the cost of operating it is $0.0081 per hour. From the information give, I came up with the linear equation: Let c be total cost and Let h be hours used. Therefore: c = 0.0081h + 0.75 represents the total cost of the light bulb and the electricity. However, the second part of the question added the fact that the light bulb will only last for 800 hours. If the light bulb is replaced as soon as it burns out exactly after every 800 hours, how can I write an equation that represents that? Is it possible? What would it look like on the graph. Harley Weston lui répond. 





Connecting to a water line 
20001020 

Vanja pose la question : My question is...A house is to be connected to a new water main that runs along the line y=2/3x1. The connection point at the house has coordinates (2,9), where the units represent metres. What lenght of plastic pipe is needed to connect to the water main at the closest point? Penny Nom lui répond. 





2step equations 
20001011 

Jen pose la question : i don't get how you find the answer to these equations 140= 4 12e x/2 + 6 = 4 Penny Nom lui répond. 





Buying art supplies 
20000918 

Travis pose la question : An art teacher buys exactly 100 items at this sale, and the total cost before tax is $100. She buys at least one of each item. How many of each item does she buy? Markers $0.50 Sketch Pads $3.00 Paint Sets $10.00 Denis Hanson lui répond. 





Two linear equations 
20000914 

David Dean pose la question : 2a + 1b = 3.39 3a + 3b = 6.59 What formula do I use to find what a = ? Harley Weston lui répond. 





Two linear systems 
20000801 

A student pose la question : please help me with this homework question. 5/x + 6/y= 19/6 3/x + 4/y =2 hint: let a = 1/x and b = 1/y substitute these expressions into the system to find a and b. Then find x and y. This is a question I answered wrong on a test: solve the given system for x, y, and z. Express your solutions in terms of a, b, and c. Penny Nom lui répond. 





n! = 42(n2)! 
20000721 

Damon Bailey pose la question : Solve n! = 42(n2)! Paul Betts lui répond. 





The equation of a parabola 
20000522 

Ian Forsyth pose la question : Given the points A(0,0) B(60,10) C(24,d) find the equation of the parabola. leave the equation in terms of x, y and d if the general form of a quadratic is y = ax^{2} + bx + c. Penny Nom lui répond. 





A matrix equation 
20000514 

A student pose la question : Right now, we are dealing with matrices and we are supposed to solve the following problem on our graphingcalculators: 2a+3b4c+d=20 a2b+3c5d=14 3a+4b2c+3d=19 5ab+6c+4d=5 Penny Nom lui répond. 





Taxis in Chicago 
20000327 

A high school studenthigh school student pose la question : Suppose that taxis pick up and deliver passengers in Chicago, which is divided into three zones. Records kept by the drivers show that of the passengers picked up in Zone 1, 50% are taken to a destination in Zone 1, 40% to Zone 2, and 10% to Zone 3. OF the passengers picked up in Zone 2, 40% go to Zone 1, 30% to Zone 2, and 30% to Zone 3. Of the passengers picked up in Zone 3, 20% go to Zone 1, 60% to Zone 2 and 20% to Zone 3. Suppose that at the beginning of the day, 600 of the taxis are in Zone 1, 100 in Zone 2, and 300 in Zone 3. What is the distribution of taxis in the various zones after all have had two riders? Harley Weston lui répond. 





A system of equations in five unknowns 
20000320 

Will pose la question : I have been having some problem with the following question for some time. I would appreciate any help on solving the problem or a solution. Q: Assume that a system of equations in the unknowns x1, x2, x3, x4 and x5 when converted to row echelon form gives . . . Penny Nom lui répond. 





Simultaneous equations 
20000311 

Laura Molck pose la question : My name is Laura Molck and I am in Year 11 in Australia. Please help me with the following. I know that they are all simultaneous equations which I can do but I have trouble with the formulae to work the equations. Can you please help!! 1. A tent manufacturer produces 2 models, Outback and Bushwalker. From earlier sales records it is known that 20% more of the Outback model is sold than the Bushwalker. A profit of $200 is made on each Outback sold, but $350 is made on each Bushwalker. If during the next year a profit of $177,000 is planned how many of each model must be sold? Penny Nom lui répond. 





Systems of linear equations 
20000310 

Ann Marie Devereux pose la question : hi there!!, I guess I have a problem!!! 3x+4y=10 (over) 4x+y=9 2x=5y+3 (over) x=3y+1 Penny Nom lui répond. 





Some equations 
20000308 

Maria pose la question : Hi, could you help me with these questions: Find x & solve  72x/3=9
 4x+3/5=2
 62x=14
 1/7x=4/3+1/6
Penny Nom lui répond. 





A mixture problem 
20000306 

Rebecca Edwards pose la question : A tank in which cholocate milk is being mixed contains a mixture of 460 liters of milk and 40 liters of chocolate syrup initially. Syrup and milk are then added to the tank at the rate of 2 liters per minute of syrup and 8 liters of milk per minute. Simultaneously the mixture is withdrawn at the rate of 10 liters per minute. Find the function giving the amount of syrup in the tank at time t. Harley Weston lui répond. 





Midpoints and endpoints 
20000215 

Jessica Sipes pose la question : I need to know how to find and endpoint using the midpoint and the other endpoint. Penny Nom lui répond. 





Quadratic 
20000126 

Karen Johnson pose la question : What is the reasoning behind the title quadratic equation? Penny Nom lui répond. 





Ax + By = C 
20000118 

Fatiha Khanboubi pose la question : I was wondering if you could please explain to me how I would write the equation of line through the given points [(4,1), (6,3)] in Ax+By=C form. Harley Weston lui répond. 





Parallel lines 
20000112 

Lori pose la question : Find an equation of the line parallel to the given line containing the given point. x + y = 2; (1,2) We know parallel line have the same slope and we know the answer y = x + 3. Penny Nom lui répond. 





Solve for v 
19991209 

Beth pose la question : 13/4(v+2)=5 Penny Nom lui répond. 





Systems of equations 
19991206 

Roger Hornbaker pose la question : I am having problem figuring out x and y solutions.  5x + y = 4
3x  y = 4  3x + 2y = 6
 3x + y = 0 Penny Nom lui répond. 





The elimination method 
19991202 

Jennifer pose la question : Could I get an answer to this one: 2x+5y=36 3x+2y=32 I have to use the Elimination method, as I already know how to do Substitution. How do I begin and show my work? I'm attempting to eliminate the values for y. Penny Nom lui répond. 





How wide is the well? 
19991124 

Chris Baranski pose la question : There is a well and in the well there are 2 sticks one is 2 meters long the other is 3 meters long and they are opposite to each other. They are leaning against the wall of the well. The place where they touch is 1 meter of the bottom of the well. How wide is the well? Chris Fisher lui répond. 





Linear models 
19991109 

Helen Moreno pose la question : What is a linear model? Harley Weston lui répond. 





Multiple step problems 
19991109 

Maria Rainsdon pose la question : I don't understand how to solve these multiple step problems. I wasn't there when my teacher explained it and I am really lost. Here is one of the probs I don't understand: 3m+6=m6. Penny Nom lui répond. 





Equations with fractions 
19991010 

Lori pose la question : I'm a secondary student. How would you figure out a problem such as t2/t =14/3t  1/3. The book gave one example but it is really easy. The work YOU have to do is totally different. You don't have to tell me the answer just how to do such problems like these. Penny Nom lui répond. 





Why is slope designated m? 
19990818 

Peter Komlos pose la question : Why is the slope of a line is designated by the letter "m"? Penny Nom lui répond. 





Parametric Equations 
19990806 

Nicholas Lawton pose la question : Show that an equation of the normal to the curve with parametric equations x=ct y=c/t t not equal to 0, at the point (cp, c/p) is : yc/p=xp^2cp^3 Harley Weston lui répond. 





Graphing a linear equation 
19990527 

Dylan Bradley pose la question : Im in Grade ten and am doing linear equations, I cann't figure out how to make a chart for questions like y = 2x + 3 Penny Nom lui répond. 





Question about 3rd degree polynomials 
19990423 

Patrick Bryan pose la question : What is the general solution to the equation with the form: a*x^3 + b*x^2 + c*x + d = 0 I have once seen a solution to this a few years ago, but I do not recall if it was a general solution. What I do know, is that you could simplify this equation to: a*x'^3 + p*x' + q = 0... Doug Farenick lui répond. 





Parallel and perpendicular lines 
19990423 

Crystal Pilling pose la question : My name is Crystal Pilling and I am in 9th grade algebra. We are currently studying parallel and perpendicular lines. I am having trouble with this problem: 3/4x  5y= 16, (5,6) I have to find a line that is perpindicular to this line on a graph. HELP ME PLEASE!!!!! Penny Nom lui répond. 





Shopping at Wegman's 
19990422 

Stan pose la question : Joanne, Steve, Pat, Alice, Joan, and Bill go to Wegman's at the same time. Joanne buys 2 gal of milk, 1 dozen oranges, 8 apples, and 2 lb. of ground beef, paying a total of $13.24. Steve buys 3 qts. of milk, 5 lbs. of ground beef, 10 lb. of potatoes, and 2 bags of mixed vegetables, paying a total of $16.95. Pat buys 3 gal. of milk, 2 dozen oranges, 1 dozen apples, 5 lb. of potatoes, and 5 bags of mixed vegetables, paying a total of $25.09. .... Find the cost of: 1 qt. of milk, one orange, one apple one lb. of ground beef, one lb. of potatoes, and one bag of mixed vegetables. Penny Nom lui répond. 





A ladder problem 
19990422 

Michael Blade pose la question : There is a cube box 3feet x 3feet x 3ft resting against a vertical wall on level ground. Resting against the outside corner of the box is a ladder 10 feet tall, this ladder is of course resting on the ground but also against the outside corner of the box and rests on the wall. The question the ladder is divided into two unequal section bounded by the box to the ground and the box to the wall. what are those dimensions? Penny Nom lui répond. 





Quadratic equations 
19990331 

Ken Niebergall pose la question : #1 a^{2}  10a = 2a  36 #2 t(t  5) = 5 (t  5) #3. (x + 4)(x  3) = 8 Thanks. Jack LeSage and Penny Nom lui répond. 





Standard Form 
19990330 

Pam pose la question : How do you put this equation into standard form? y=3.572x+5.409 Would you please put this equation in this form Ax+Dy+C=0 Penny Nom lui répond. 





Linear Equations 
19990116 

Casie Tomney pose la question : My dad and I have been trying to figure, how to solve for x on any of these problems my teacher gives us. The problem is: 2h/3 + 1/2 = 5h/6  3/4 Thanks!!!!!!!! Jack LeSage lui répond. 





Intersection of Planes 
19981203 

Lindsay Fear pose la question : My name is Lindsay Fear. I am an OAC student (which is the Ontario equivalent to Grade 12 in most other states and provinces). I am in an Algebra and Geometry course and am currently studying a unit on equations of planes. Our teacher has given us this question that my friend and I have attempted several times, but we are still unable to solve it. My teacher has also suggested using the internet as a resource. The question is: Prove that a necessary condition that the three planes x + ay + bz = 0 ax  y + cz = 0 bx + cy  z = 0 have a line in common is that a^2 + b^2 + c^2 + 2abc = 1 Walter Whiteley lui répond. 





Algebra 
19981125 

Casey pose la question : yeah my son brought home a math worksheet and he was wondering and me too if u could help him and me out . he has problems like this 4n+9=7n+2= ??? and he has to show work so if u could help us out that would be great Jack LeSage lui répond. 





Linear systems of equations 
19981116 

Crystal Girvan pose la question : My name is Crystal Girvan.Im in grade 11. I have a question.We are solving linear systems of equations: comparison method. My questions is. it says a)use the method of comparison to solve this system a=b1, 3a+ b=3 b) verify your solutin in a I dont understand it. please help Jack LeSage lui répond. 





The Left Side of a Parabola. 
19981020 

Shay pose la question : Find the parametrized equation for the left half of the parabola with the equation: Y=x^24x+3 Chris Fisher lui répond. 





A Linear System 
19981008 

Jason Bussey pose la question : The linear systems with the following pattern all have the same solution. Is their some kind of reasoning as to why this is so? 2x+3y=4 3x+4y=5 4x+5y=6 5x+6y=7 The solution is always x=1, y=2 Thank you Jason Penny Nom lui répond. 





Grade 9 Algebra 
19980607 

Tarah Kostenko pose la question : I am a grade 9 student and I cannot figure out how to solve these two similar problems. can you please help? 3(y1/2)=1/2 also 2/3(x + 1)=6 I don't come up with the same answers as the book and I can't figure out what I'm doing wrong. Thank you,
Harley Weston lui répond. 





Graph question 
19980512 

Rose Seminary pose la question : Why is the point of intersection of two lines the solution to the corresponding system of equations? Penny Nom lui répond. 





Seed Problem 
19980326 

Jody A. Johnson pose la question : Seed Problem: The height of an amazing plant grown from a seed varies linearly with the time it has been in the ground. After six days it is 6cm tall and after 60 days it is 15.8m (1580 cm) tall.  Write the particular equation giving the height as a function of time.
 Find the intercepts and explain them.
 What would be the height in one year?
 How long would it take for the plant to grow to a height of 1km?
I'm having a problem with this equation. Could you please help. Thank you. Penny Nom lui répond. 





Yintercept 
19980227 

Don Trumpet pose la question : What is the Yintercept for the problem:Y = 2(x+2) + 9 Harley Weston lui répond. 





Intersecting Lines. 
19980210 

Erik Heppler pose la question : My typewriter frequently makes mistakes. Suppose I gave you the following system of equations to solve: 35.26X + 14.95Y = 28.35 187.3X + 79.43Y = 83.29 When I looked back, I realized that I meant to use 14.96 as the "Y" coefficient in the first equation instead of 14.95. Solving the system using 14.95 and then solving another system using 14.96 with all other values the same both times results in the intersection points (1776, 4186) and (770, 1816) respectively. How can that be? Penny nom lui répond. 





Find the Numbers. 
19971228 

Sandy C pose la question : The sum of the squares of two numbers is 53. Twice the greater, minus the lesser is 11. Find the numbers. Penny Nom lui répond. 





Equation of a line 
19970408 

Susan Gregson pose la question : I am a secondary school teacher. My students and I would like to know why the letters m and b are traditionally used to stand for slope and Yintercept in the standard form of an equation. Was this an arbitrary choice? Who made it? Are the letters from Greek ot Latin words? Harley Weston lui répond. 





A Functional Equation. 
19970226 

Ronald Lui pose la question : Find all functions f:S > S statisfying the two conditions: 1)f(x+f(y)+xf(y))=y+f(x)+yf(x) for all x and y in S 2)f(x)/x is strictly increasing on each of the interval 1 Saroop Kaul and Chris Fisher lui répond. 





Cardano's method 
19960311 

Mike Gorski pose la question : What is Cardano's method for finding the roots of a cubic equation? Harley Weston lui répond. 

