







Pre tax and post tax percentages 
20180522 

Tom pose la question : Hi,
I work in a clothes shop which can also do mailorders. My Head Office
has sent a report with which we can check the records we keep in store
tally with those at HO.
According to that report we have taken £2578.25 in orders, excluding VAT (20%),
which would therefore be £3093.91 including VAT (2578.25+20%=3093.91).
According to my records, we have taken £3179.32 including VAT, which would be
£2543.45 excluding VAT (3179.3220%=2543.45).
Why is it that the difference between the VAT inclusive figures (3179.323093.91) is +£85.41, but
the difference between the VAT exclusive figures (2543.452578.26) is £34.81?
Now, I can see from the report that 1 order has not been recorded by HO, and I
know that our average order value is around £30, so the £34.81 makes sense.
But surely both figures should be a minus, regardless of whether they include VAT?
I'm sure there is an obvious answer, but I just cannot see it! Any help would be gratefully
received.
Thanks,
Tom Penny Nom lui répond. 





The sum and difference of two numbers 
20180313 

samima pose la question : Two numbers have a difference of 0.85 and the sum 1.What are the numbers? Penny Nom lui répond. 





Expand (5x9)(5x+9) 
20180301 

adil pose la question : expand the following:
(5x9)(5x+9) Penny Nom lui répond. 





The sum and difference of two numbers 
20180125 

Ali pose la question :
Hello,
I was looking at the original question that was posted and answered by
your team:
http://mathcentral.uregina.ca/QQ/database/QQ.09.07/s/donna1.html
I used the 7 and 4 as example and not looking for 39 per original
question:
A=7
B=4
7+ 4 =11 and 74 = 3
We end up with 11 +3 = 14
A= 14/2 give use 7
B = how do you solve for B or 4 with out knowing anything about 3 or any other numbers ?
Thank you
Ali Penny Nom lui répond. 





An arithmetic sequence 
20171130 

yo pose la question : x; 2x+1; 11 are three consecutive terms of an arithmetic sequence.calculate x Penny Nom lui répond. 





An arithmetic sequence 
20170717 

abbi pose la question : hi there im a student in 11 grade
ive been trying to do this task but i have no idea how to do it
the question is
Find the common difference and the n^th term of the arithmetic sequence if the first term is 4 and the twentieth sum of the terms is 1030 Penny Nom lui répond. 





Successive Differences 
20170406 

Twaha pose la question : Please find the equation of the sequence 1 2 4 7 11 16 22 Penny Nom lui répond. 





The sum and difference of two numbers 
20170320 

Olivia pose la question : The sum of two numbers is 87 and their difference is 29. What are the two numbers Penny Nom lui répond. 





1/1cosine(2x)  1/1+ cos(2x) 
20161214 

Sean pose la question : 1/1cosine(2x)  1/1+ cos(2x) Penny Nom lui répond. 





A pattern rule for a sequence 
20161028 

Grace pose la question : Here's a Grade 7 question, we need to find the pattern rule:
1  1
2  3
3  6
4  10
......
It may involve exponents, but we can't seem to figure it out.
thank you.
Grace. Penny Nom lui répond. 





A sequence 
20160105 

Mia pose la question : the next three terms in each sequence. 0.4, 0.54, 0.68, 0.82, Penny Nom lui répond. 





2^48  1 
20150613 

Soham pose la question : The number 2^481 is divisible by two numbers between 60 and 70. The sum of
the two numbers is? Penny Nom lui répond. 





A limit 
20150219 

genc pose la question : Lim (27x^31) / (3x1)
X> 1/3 Harley Weston lui répond. 





A difference quotient 
20150112 

Sasha pose la question : Simplify the difference quotient
f(x) − f(a)/ xa
if x ≠ a.
f(x) = x^3 − 12
Penny Nom lui répond. 





(x3)^2(x+3)^2 
20141113 

Bernice pose la question : (x3)^2(x+3)^2 Penny Nom lui répond. 





An arithmetic sequence 
20140320 

Xabiso pose la question : The 10th term of an arithmetic sequence is 28 and the 7th term is 19. Calculate the common difference and the first term of the sequence. Penny Nom lui répond. 





Can 100r^281z^2 be factored? 
20131208 

Rosa pose la question : Can 100r^281z^2 be factored? Penny Nom lui répond. 





An Arithmetic Progression 
20131008 

collins pose la question : In an A.P. the difference between the 8th and 4th term is 20 and the 8th is one and half times the 4th term... what is the common difference and the first term Penny Nom lui répond. 





Constructing a triangle 
20130822 

Nazrul pose la question : The base, the difference of the angles adjoining the base and the sum of the other
two sides are given. How can I draw the triangle?
Please help me. Chris Fisher lui répond. 





a cubeb cubea+b= ? 
20130616 

saryu pose la question : a cubeb cubea+b= ?
find the answer Penny Nom lui répond. 





Two numbers whose difference is 16 
20130608 

Johan pose la question : Two numbers whose difference is 16 and whose sum is 120 Penny Nom lui répond. 





(4 4cos^4 x)/(sin^2 x) 
20130518 

Agnes pose la question : How I can solve this question :
Simplify (4 4cos^4 x)/(sin^2 x) and write in terms of sin x Penny Nom lui répond. 





An algebraic exercise 
20130318 

autumn pose la question : given: f(x)=x/(x^2+2) determine: [f(xh)f(x)]/h Penny Nom lui répond. 





Difference of squares 
20121119 

Qelibar pose la question : Please factorise x^2y^2  4 Penny Nom lui répond. 





The difference of the numbers on two dice 
20120819 

dilys pose la question : Two fair dice are thrown. Find the probability that the difference of the two numbers is divisible by 4? Chris Fisher and Lorraine Dame lui répond. 





Two equations involving fractions 
20120612 

Fatima pose la question : Hi ,teacher gave two question to my daughter as follows
Solve 2/x+3=(1/xx9)(1/x3)and
Solve (4/x2)(x/x+2)=16/xx4
Please help me
Thanks & regards fatima Penny Nom lui répond. 





The difference in latitudes of two cities 
20120118 

Renee pose la question : Assuming that the earth is a sphere of radius 6378 kilometers, what is the difference in latitudes of two cities, one of which is 600 kilometers due north of the other? Robert Dawson lui répond. 





Sum and difference of squares 
20111231 

Anne pose la question : Se x e y são números reais distintos, então:
a) (x^2 + y^2) / (x  y) = x + y
b) (x^2 + y^2) / (x  y) = x  y
c) (x^2  y^2) / (x  y) = x + y
d) (x^2  y^2) / (x  y) = x  y
e) Nenhuma das alternativas anteriores é verdadeira. Harley Weston 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. 





Find two numbers whose difference is 153. 
20110510 

Scott pose la question : Find two numbers whose difference is 153. Penny Nom lui répond. 





(3x+4y)^2  (2xy)^2 
20110316 

Taiwo pose la question : pls could some one help me with this question? thanks as lot
factorize:
(3x+4y)^2  (2xy)^2 Penny Nom lui répond. 





Difference quotient 
20100726 

Brandon pose la question : i'm trying to figure out how to use the difference quotient with x^3, i have tried the following...(x+h)^2*(x+h)(x+h)/h and i have only gotten as far as...(x^2+2xh+h^2)(x+h)/h....i cannot see where i am goin astray, i know i am overlooking something simple, what am i overlooking? Penny Nom lui répond. 





Difference of cubes 
20100522 

Anad pose la question : how can we prove a^3  b^3 is equal to (ab)(a^2+ab+b^2)? Penny Nom lui répond. 





(9  x^2)/(x  3) 
20091204 

Sandy pose la question : 9x^2/x3
I need to know how to solve this.
Thanks Penny Nom lui répond. 





Successive differences 
20090618 

Jonathan pose la question : I'm trying to find the next number sequence for this equation: 1 11 35 79 149 251, my problem is that I worked it out and ended up with a single number 17. What am I doing wrong. Thank you for any help. Robert Dawson and Penny Nom lui répond. 





A difference quotient 
20090617 

Sue pose la question : When s(x)=x^3+x, compute and simplify the difference quotient s(x+h)s(x)/h. Harley Weston lui répond. 





Actual Food Cost is 3% or more above Projected Food Cost 
20090407 

Kam pose la question : Your store guidelines states that when Actual Food Cost is 3% or more above Projected Food Cost, immediate corrective action be taken by the Unit Manager. In January, your Actual Food Cost was $11,000, and your Projected Food Cost was $10,850. To find out what percentage the difference is do I divide the difference ($150) by Actual Food Cost ($11,000) or Projected Food Cost ($10,8500)? What would be the answer? Thanks Harley Weston lui répond. 





Percentage difference in pipe volumes 
20090222 

mike pose la question : what is the % difference between a 3 inch diameter pipe compared to a 4 inch diameter pipe? and how do i find the answer? Penny Nom lui répond. 





The difference quotient (f(x+h)f(x))/h 
20090126 

helen pose la question : Find the difference quotient of f, f(x+h)f(x)/h, h does not equal 0, for this function. Be sure to simplify. that is, find f(x)=x^2x+4 Robert Dawson lui répond. 





Factor x^2  y^2 
20090120 

Shell pose la question : complete Factor: x^2y^2 Penny Nom lui répond. 





Determining the Unknown Numbers 
20081206 

jacob pose la question : the sum of two numbers is 45 and their difference is 15. what are the two numbers? Janice Cotcher lui répond. 





Factoring 
20081119 

Neji pose la question : How do you factor (yz) (y+z) (y^4+y^2z^2+z^4) and get (y+z)(y^2yz+z^2) (yz) (y^2+yz+z^2) as the answer? Harley Weston lui répond. 





z(z+1)x(x+1) / zx 
20080930 

sylvia pose la question : z(z+1)x(x+1) / zx
HOW DO I SIMPLIFY THIS Penny Nom lui répond. 





a(a+1)  b(b+1) 
20080930 

Shaun pose la question : I need to factor (ab) out of the following: a(a+1)  b(b+1). I know it is simple but I cannot remember how. Penny Nom lui répond. 





3,6,10,15,and 21 
20080928 

jarred pose la question : i am currently stumped on a math project that requires me to find out the recursive formula for a sequence of numbers. the numbers in the sequence are 3,6,10,15,and 21. Thank you for your time. Walter Whiteley lui répond. 





A cubic equation 
20080825 

RAM pose la question : The following Cubic Eqn should have three roots  what are they?
x^327=0 Penny Nom lui répond. 





Simplifying Algebraic Expressions 
20080822 

Jacky pose la question : x^2y^2+4x+4y Penny Nom lui répond. 





Factoring x^2 + 729 
20080819 

peter pose la question : hello I,am having trouble factorising a polynomial into polynomial factors
with real coefficients please can you help the polynomial is x^2+729 Harley Weston lui répond. 





[f(x)f(1)]/(x1) 
20080814 

katie pose la question : Evaluate (if possible) the function of the given value of the independent
variable:
f(x)=(x^3)x:
[f(x)f(1)]/(x1) Penny Nom lui répond. 





Percent difference 
20080812 

mike pose la question : What is the percent difference between two homes if one is worth $525,000
and the other is $425,000. (525,000  425,000 = 100,000) Penny Nom lui répond. 





A difference quotient 
20080710 

Rita pose la question : Find the difference quotient of f, that is, find [f (x + h)  f (x)]/h, where
h does not = 0 for the given function. Be sure to simplify.
f(x) = 1/(x + 3) Janice Cotcher lui répond. 





Percent difference? 
20080614 

Cathy pose la question : I am trying to verify a "percent of difference" as stated on a tax form. I cannot seem to come up with the equation to do so.
Here are a few examples on the form:
Last year $62.91 this year $66.05 tax difference $3.14 percent difference 5.64%
Last year $ 2014.97 this year $1982.93 tax difference $32.04 percent difference 57.56%
Last year $97.66 this year $79.58 tax difference $18.08 percent difference 32.48%
I have tried several different ways and per some of Q&A's already on your site I still have a problem and would appreciate some assistance.
ThanksCathy Penny Nom lui répond. 





Percentage difference 
20080520 

Cavell pose la question : Hi, the projected cost was 71,700. The actual cost was 56,876. What is the percent difference? Penny Nom lui répond. 





5x^2  45 
20080211 

Tiana pose la question : factor:
5x^2  45 Stephen La Rocque lui répond. 





Sum and difference of cubes 
20080130 

Amanda pose la question : It has been a really long time since I was in Algebra and I can't remember how to factor cubes such as x^3 +81 or subtracting/adding fractions with variables such as [1/(x+h)+2][1/x+2]. Please help!!! Penny Nom lui répond. 





Percentage of what? 
20080123 

Jenny pose la question : What is the difference in percentage between 31990 and 29990? Stephen La Rocque lui répond. 





Explaining the factoring for the difference of cubes 
20080116 

Bill pose la question : A student asked me where did the "difference of cubes" and "sum of cubes" come from. I did not have an answer for her. She is very bright and understands how they work but wanted to know where they derived from. Any help you can offer would be great. Thanks Stephen La Rocque lui répond. 





Expand (a^4  b^4) 
20071117 

Saif pose la question : how would you expand (a^4  b^4) ??? Stephen La Rocque and Victoria West lui répond. 





The nth term 
20071018 

shannon pose la question : Ok , what i am having problems with is the nth term. I get how the numbers come together, but i am having trouble with finding the nth term. Penny Nom lui répond. 





The percentage difference between 1/20 to 1/15 
20071011 

jake pose la question : what is the percentage difference between 1/20 to 1/15.... Stephen La Rocque lui répond. 





Sum and difference of two mystery numbers 
20071004 

Donna pose la question : The sum of two numbers is 39. The difference is 11. What are the numbers? Stephen La Rocque lui répond. 





Percentage differences 
20070829 

Camilla pose la question : If a store sells a certain syle of skirt, an in the first week they sell 13,
in the second week 20, in the third week 17 and in the fourth week 23, calculate the percentage
difference between the highest and the lowest weekly sale. Stephen La Rocque and Harley Weston lui répond. 





Percentage difference between a microcentury and 50 minutes 
20070821 

Wonder pose la question : A lecture period (50 min) is close to 1 microcentury.
Find the percentage difference from the approximation? Stephen La Rocque lui répond. 





Percentage change 
20070813 

Karen pose la question : I need a formula for calculating percentages in Excel. For example, we =
sold 4 units of an item one month, and 105 units the next. I need a =
formula to calculate the percentage increase in sales units. Also, if =
5251 were sold one month and 651 the next, what is the formula for =
calculating the percentage difference? Please help, thank you. Penny Nom lui répond. 





Simplifying an algebraic fraction expression 
20070725 

Jessica pose la question : How do I simplify b/(b^{2}25) + 5/(b+5)  6/b? Stephen La Rocque lui répond. 





A statistical difference 
20070703 

a student pose la question : I am writing a paper for a grad class in which I am comparing achievement levels of boys and girls. I have data that shows the average marks for girls and boys in each grade 12 subject for the entire province.
My prof want me to show there is a statistical difference. What do I have to do to show this? I don't have access to the raw data, so don't know the SD. Is there anything I can do mathematically with the data that I have? (I can determine n for each set of data, it ranges between 2400 and about 13000 for each subject area.) Chris Fisher and Harley Weston lui répond. 





Simplifying complex denominators 
20070621 

Krys pose la question : How do I simplify completely?
((4+i ) / (3+i ))  ((2i ) / (5i )) Stephen La Rocque lui répond. 





What is the 100th term? 
20070615 

George pose la question : I have the sequence
50,120,235,406,644
the 1st difference is 70,115,171,238
the 2nd difference is 45,56,67
the 3rd difference is 11,11
i used the a*n^3+b*n^2+c*n+d rule but the a turns out to be a decimal
because 11/6 is 1.833333333 and so i cant find the formula for the 100th term
term. Penny Nom lui répond. 





The difference between two dice 
20070602 

smiley pose la question : Two standards dice are rolled. Determine the probability
that the difference between the two numbers on the dice is 2 Penny Nom lui répond. 





Percent difference 
20070517 

Carolyn pose la question : What is the % difference between these two numbers 211373 & 185420 Gabriel Potter, Penny Nom and Steve La Rocque lui répond. 





Using the "difference of squares" formula how do I compute 27 * 33? 
20070402 

Sarah pose la question : Using the "difference of squares" formula how do I compute 27 * 33? Penny Nom lui répond. 





The percentage difference between 64.24% and 74.24% 
20070303 

M pose la question : What is the percentage difference between 64.24% and 74.24%? Stephen La Rocque and Penny Nom lui répond. 





Factoring polynomials 
20070214 

Joe pose la question : I am in the eighth grade, and we are learning the equivalent of Algebra 2. I have no ides how to factor (x2)(x^21)6x6 You help is most aprreciated. Thank you! Joe Stephen La Rocque lui répond. 





Find the next 3 terms of the sequence 
20070207 

rose pose la question : find the next 3 terms of the sequence 2,3,9,23,48,87 Penny Nom lui répond. 





Factoring m^49^n 
20061207 

Josh pose la question : I can not figure out how to completely factor m^49^n. Penny Nom lui répond. 





(a^(1/3) – b^(1/3)) ( a^(2/3) + a^(1/3)b^(1/3) + b^(2/3)) 
20061024 

Julie pose la question : (a^{1/3} – b^{1/3}) ( a^{2/3} + a^{1/3}b^{1/3} + b^{2/3}) Haley Ess lui répond. 





Percentage differences 
20061023 

Michael pose la question : how do I calculate the percentage difference of a certain box size. for example. How much percent smaller is this box: 8.4mm x 6.3mm to this box: 9.35mm x 7mm Stephen La Rocque lui répond. 





Plotting percentage change 
20061011 

Beckie pose la question : I have worked out a set of percentage differences which are all percentage decrease. Should i express them as a negative percentage as 20%? I also need to plot them on a graph and am not sure whether to just use the percentage difference as it is, in which case i get a positive gradient, or include a negative axis and plot them in this way, in which case i would get a negative gradient. I think the slope of the curve will be the same either way so it might not matter! Penny lui répond. 





Percentage Difference 
20060725 

Sandra pose la question :
I have two numbers (1530 and 1315). How do I calculate the percentage difference.
For example: I have one loader that lifts 1530 lbs. and another loader that lifts 1315 lbs. I know the difference is 215 lbs. How much greater lift capacity does the loader that lifts 1530 lbs. have than the loader that lifts 1315 lbs.?
The formula that I used was:
1530  1315 = 215
215/1315 = .163498 or 16.3%
Is this correct?
Stephen La Rocque lui répond. 





Factor 
20060308 

Brad pose la question : Factor:
x^{3} + 64m^{3} and 125p^{3}  q^{6} Penny Nom lui répond. 





3x^4  81 
20060102 

Julio pose la question : How can I factor the following?:
3x^{4}  81 Penny Nom lui répond. 





A sum of 75 and a difference of 13 
20051030 

Vicki pose la question : Find two numbers that have a difference of 13 AND A SUM OF 75? We need to learn about the formula or procedure. Penny Nom lui répond. 





1242, 826, 1034, 930, 1658 
20050831 

Elizabeth pose la question : here is a math question my niece gave me, grade 7
1242, 826, 1034, 930, 1658
first day of school and this is what they give her no explanation Harley Weston lui répond. 





Difference in latitude 
20050405 

Gretel pose la question : Assuming the the earth is a sphere of radius 6378 kilometers, what is the difference in latitude of two cities, one of which is 400 kilometers due north of the other? 500 kilometers? Penny Nom lui répond. 





The answer to a subtraction problem 
20050322 

Libby pose la question : What is the name of a number that is the answer to a subtraction problem? Diane Hanson and Claude Tardif lui répond. 





"a" cubed minus "b" cubed 
20041202 

Denise pose la question : "a"cubed minus "b"cubed equal (ab) times
("a"squared plus "ab" plus "b"squared)?
I know this is a formula, but why is it true? Penny lui répond. 





Factoring 
20040719 

A student pose la question : Factor completely:
3x3  24y3
54x6 + 16y3
16xy  4x  4y  1
0.09x2  0.16y2 Penny Nom lui répond. 





3x squared  27 / x + 3 
20040504 

Stef pose la question : 3x squared  27 / x + 3 Penny Nom lui répond. 





Some factoring problems 
20040415 

KJ pose la question : Factor these:
x^{3}+125 > (x+5)^{3}
8x^{3}27 > (?)
x^{2}+36 > (x+6)^{2}
x^{4}5x^{2}+4 > (?) Penny Nom lui répond. 





Percent difference 
20040410 

A parent pose la question : For a school science project, my son Alex is taking measurements of plant growth at regular intervals. As part of the data, he must provide the maximum percent difference observed in the categories his team has identified.
So, for example he has six plants with four measurements each. (He has more, but I'll keep it simple) For the first plant he measured 2mm, 2.4mm, 2.9mm, and 3.2mm. For the 2nd, 3rd, and 4th plants, he has similar numbers. Is there a way to calculate the maximum percent difference between any two plants in his measurements during the project? Doing it for each combination would be tedious. Penny Nom lui répond. 





Differences in percentages 
20040406 

Jose pose la question :
Question:
You have two groups:
Group A has 10 people and 2 are Chinese
Group B has 12 people and 3 are Chinese
In terms of percentages what is the difference in Chinese between the two groups? In other words which group has the biggest percentage of Chinese and why?
Penny Nom lui répond. 





Percentage difference 
20040328 

Someone pose la question : what is the percentage difference between 157 to 251 Penny Nom lui répond. 





Sums and differences 
20040210 

David pose la question : The sum of two whole numbers is 63. The difference between the numbers is 10. Find all the possible pairs. Claude Tardif and Penny Nom lui répond. 





Difference of squares 
20031124 

Susie pose la question :
Factor assuming that n is a positive #
Problem: (I will give it to you in words beacuse I don't know how to do exponents on the computer.)
Fortyfive r to the 2n power minus five s to the 4n power.
I was hoping you could walk me through it not just give me the answer.
Penny Nom lui répond. 





The 4th difference 
20031117 

Jack pose la question : If i had a sequence which was the same at the 4th difference, aka difference
to the 4th, like:
1 5 14 30 56 96
(sequence)
4 9 16 26 40
5 7 10 14
2 3 4
1 1
then what would be the set formulars to find out a, b, c, d, and e
as i know the equation has to be an^{4}+bn^{3}+cn^{2}+dn+e Penny Nom lui répond. 





Is 3/5 CLOSEST to 0, 1/2 or 1? 
20030709 

A student pose la question : I would like to know is 3/5 CLOSEST to 0, 1/2 or 1. And can 3/10 go either way as to be closest to 0 or 1/2. Penny Nom lui répond. 





The sum of two numbers is 5 and their difference is 
20030616 

Akhil pose la question : The sum of two numbers is 5 and their difference is 11. What is the product of the two numbers? Penny Nom lui répond. 





Finite differences 
20030210 

Jenny pose la question :
I need to find a formula that will work with any number. I am finding the volume of a 3d cross shape. Here are my results so far:
Term Number 0 1 2 3 4 5
nth term 1 7 25 63 129 231
1rst diff 6 18 38 66 102
2nd diff 12 20 28 36
3rd diff 8 8 8
I can't seem to find a formula that will work with any number. Any help would be much appreciated. Penny Nom lui répond. 





Factoring 
20021211 

Larry pose la question : Question:
how do u factor trinonmials
EX: X^{ 3} + Y^{ 3}
X^{ 3}  8Y^{ 3}
8X^{ 2}  72
64A^{ 3}  125B^{ 6} Penny Nom lui répond. 





Percentage 
20020720 

Sally pose la question : If 20% of 100 is 80, then why is the percentage difference between 80 and 100 25%. Penny Nom lui répond. 





Percentage difference 
20020308 

Tedd pose la question : Can you give me the formulas for calculating percentage differences between two numbers? For example: if the first number is 10 and the second number is 15, then the second number is 50% larger than the first number. However, the formula to calculate that percentage won't work if the first number is greater than the second number as in the following example: The first number is 15 and the second number is 10, with the second number being 33.3% less than the first number. Or maybe I'm mistaken and the same formula will work in both situations. Penny Nom lui répond. 





Successive differences 
20020120 

Linsey pose la question : what is the rule for working out the formula for a sequence with three lines of difference? eg.
1, 3, 7, 15, 29
1st line differences: 2, 4, 8, 14
2nd line differences: 2, 4, 6
3rd line differences: 2, 2 Penny Nom lui répond. 





Some algebra 
20011015 

James pose la question : I cannot figure these out I was wondering if you could help me? I have no one to answer my questions.  (7x^{2} – 3yz)^{2} – (7x^{2} + 3yz)^{2}
 Use Pascal’s triangle to expand (2x – y)^{4}
 8x^{3} y  x^{3} y^{4}
 (m + 3n)^{2} – 144
 12x^{4} y – 16x^{3} y^{2} – 60x^{2} y^{3}
 p^{3} q^{2} – 9p^{3} + 27q^{2} – 243
Peny Nom lui répond. 





Finite differences 
20011008 

Murray pose la question : My name is Murray and I am a 10th grade student. Me and my friend have recently discovered and proved a theorem of a relitively advanced nature. It is that the the nth difference of an nth degree equation = n! times the coefficient of the highest power. One of my teachers said this theorem is part finite and that she thinks she has seen it before, but she does not remember what it is called, at what level it is taught, who discovered it or when it was invented. I would greatly appretiate answers to any of these questions. Chris Fisher lui répond. 





Difference of Squares 
20010222 

BrunoPierre pose la question : I noticed the other day that if you substract two consecutive squared positive numbers, you end up with the same result as if you add up the two numbers. Ex. 5 and 6 (2 consecutive positive numbers) 5^{2} = 25 6^{2} = 36 36  25 = 11 (Substraction of the squared numbers) 5 + 6 = 11 (Sum of the numbers) A more algebric view: a^{2}  b^{2} = a + b where a and b are consecutive positive positive numbers. (b = a + 1) I wondered if this rule had a name, and who discovered it. Penny Nom lui répond. 





Difference of squares 
20010220 

Janna pose la question : Hi! I was just wondering how you would factor x^{2}  9y^{2}. Harley Weston lui répond. 





Factoring (uv)^{3}+vu 
20001215 

A parent pose la question : I am a middle school teacher and a parent. I am snowed in and trying to help my 9th grader get ready for 9 weeks exams. I have tried to factor this problem to no avail. (uv)^3+vu. I have the answer but I need to know how it is done. Penny Nom lui répond. 





Factoring ^6 
20000103 

Athena pose la question :
my name is Athena and I have a question on factoring: how would you figure this out: (x^{6}y^{6}) and (x^{6}+y^{6}) Penny Nom lui répond. 





The greatest possible difference 
19990917 

Denea Hugunin pose la question : Use each of the digits 1 to 5 once to make a 2 digit number and a three digit number that the greatest possible difference. Penny Nom lui répond. 





A difference of squares problem. 
19990724 

Michael and Stephanie Bixler pose la question : If you have the equation x= n^{2}  m^{2} (ie 40= 7^{2}3^{2}= 499) x must = a positive number 1) which squared numbers work as n and m 2) how does it work 3) if my teacher gave me the number for x; how could I figure out this problem Harley Weston lui répond. 





Introductory Algebra 
19990519 

Pat pose la question : (2 + sq. root of 3) x (2  sq. root of 3) = 1 Please show me the work. Harley Weston lui répond. 





Factoring 
19990330 

Maggie Stephens pose la question : I don't know anything about factoring would you plese help me. 3x^{4}  48 54x^{6} + 16y^{3} 1258x^{3} 12x^{2}  36x + 27 9  81x^{2} a^{3} + b^{3}c^{3} I would greatly appreciate any help you can give me thanks. Jack LeSage lui répond. 





Factoring 
19990308 

L. Sivad pose la question : Question: m^{2}+6m+9n^{2} Penny Nom lui répond. 





Finding a rule for a sequence 
19990217 

Lindsey Masters pose la question : I'm doing a maths investigation and i have a sequence which goes: 13,16,25,32,45,56,73. Our teacher told us we have to find a rule by looking at the differences of the terms until we find a constant. The first differences are: 3,9,7,13,11,17. The differences of these are: ...... Please could you tell me how to work it out so that I could work out the rules of similar sequences. Penny Nom lui répond. 





What's the next term? 
19981112 

Ilia pose la question : What the formula and explonation for formula for next patterns: 1) 1, 4, 10, 20, 35, 56, 84,... 2) 0, 6, 30, 90, 210, 420,... Thanks! Penny Nom lui répond. 





Difference of squares 
19980623 

Kristen Smelsky pose la question : Solve the following using a difference of squares: 4x(squared) minus 4xy plus y(squared) minus m(squared) plus 2m minus 1 Penny Nom lui répond. 

