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Two sunflowers 2015-03-12
Maurice pose la question :
Sam and sally planted two sunflowers.Each sunflower grows 1cm each day. Sally's sunflower is 4cm high. Sam's is 12cm high. How high will each sunflower be when Sam's sunflower is twice the height of Sally's?
Penny Nom lui répond.
Constructing a cone 2015-03-12
Levi pose la question :
While the mathematics at the welding shop page was very helpful there is one vital part missing. If I have never built a cone how do I figure out how much bigger the diameter of my circle has to be when laying flat on the floor verses the diameter when it has been pulled into a cone.
Harley Weston lui répond.
The height of an equilateral triangle 2015-03-12
anna pose la question :
I am anna and i am in 7th grade.
i am trying to find the height of and equilateral triangle, all sides equaling 4 inches

Penny Nom lui répond.
The volume of a trench 2015-03-11
Kim pose la question :
A trench 60m long and 15m deep, 12m wide at the top and 8m wide at the bottom.How many cubic meters of earth have been removed?
Penny Nom lui répond.
The area of a quadrilateral 2015-03-11
Joel pose la question :
Diagonal ac of quadrilateral ABCD is 60cm and the lengths of perpendiculars to It from the opposite vertices are 4.2cm and 5.8 cm find the area of the quadrilateral ABCD
Penny Nom lui répond.
What is 1000 billion billion? 2015-03-10
LeRoy pose la question :
what does this mean? 1000 billion billion
Penny Nom lui répond.
Two consecutive odd integers 2015-03-09
gowtham pose la question :
The sum of two consecutive odd integers is 20.find the integers
Penny Nom lui répond.
Angles of elevation and depression 2015-03-08
Timmy pose la question :
Joel is walking down a street and sees a 115 ft tall building in front of him. He stops 190 feet from the base of the building at the tip of the building's shadow. Round answers to three decimal places.

A. If there was a piece of rope from the top of the building to Joel, how long would it be?
B. What is the angle of elevation from Joel to the top of the building?
C. Margaret says that she could find the angle of depression from the top of the building to Joel by subtracting the angle of elevation from 90°. Is she correct? Explain.

Penny Nom lui répond.
Extraneous solutions 2015-03-07
Emily pose la question :
I have a question about Extraneous Solutions, Because I was recently researching to figure out on how to determine that a solution is extraneous and many of the answers talked about how if a answer is negative that it should always be extraneous but now I found out that positive solutions can also be considered as extraneous solutions so that is why I am really confused Extraneous Solution's.
I would really appreciate it if you could clearly explain to me how to determine an extraneous solution from a normal solution.
Thanks,
Emily

Chris Fisher lui répond.
The definition of percent ( % ) 2015-03-07
Kenneth pose la question :
Hello:

I saw this definition online from the Free Dictionary (The Free Dictionary.com) regarding the definition of percent (%):

"Noun 1. a percent sign - a sign (`%') used to indicate that the number preceding it should be understood as a proportion multiplied by 100."

What is this "proportion" multiplied by 100?

When I think of a proportion, I think of a/b = c/d. How can a number preceding the percent sign be understood as a proportion X 100? I thank you for your reply!

Chris Fisher and Claude Tardif lui répond.
A lot on a cul-de-sac 2015-03-06
ana pose la question :
Julie lives on a cul-de-sac and wants to know if the city calculated the area of her plot of land correctly (see diagram below). We can assume the cul-de-sac is a circle and it has radius 40 feet.The boundary of the lot along the cul-de-sac (the arc from A to B) is 78.21 feet. The city found the area to be 7012.5 square feet–are they correct?
Penny Nom lui répond.
A man is standing on top of a building 2015-03-06
kiki pose la question :
a man of height 1.5m standing on top of a building of height 48.5m views another building across the square. he observe that the angle of depression of the bottom of the building is 40 degrees and the angle of depression of the top of the building is 5 degrees. Both buildings stand on the same level
a) calculate the distance of the man from the base of the building across the square measured along the line of sight

Penny Nom lui répond.
Two parallel tangents to a circle 2015-03-05
Samantha pose la question :
The equation of a circle is x^2+y^2=25. Determine the equation of the parallel tangent lines to this circle, for which the slope is 4/3.
Penny Nom lui répond.
Integers in different bases 2015-03-05
Michael pose la question :
Let k be a positive integer so that 28 (subscript)k = 132 (subscript)5
Penny Nom lui répond.
The length of a ramp 2015-03-05
Jaylynn pose la question :
Hi, I've been trying to figure out how long my ramp would have to be in order to reach a height of 3.5 feet at a 30 degree angle for a sugar glider enclosure?
Penny Nom lui répond.
 
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