SOLUTION: Express the area (A) of a rectangle with perimeter 100 feet as a function of the length (L) of one of its sides.

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Question 170574: Express the area (A) of a rectangle with perimeter 100 feet as a function of the length (L) of one of its sides.
Found 2 solutions by Mathtut, nerdybill:
Answer by Mathtut(3670) (Show Source):
You can put this solution on YOUR website!
A=L*W
P=2L+2W--->100=2L+2W--->2W=100-2L---->W=(100-2L)/2=50-L...now plug W's value into the area formula.
:
A=L(50-L)
:

Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website!
Express the area (A) of a rectangle with perimeter 100 feet as a function of the length (L) of one of its sides.
.
Normally, for a rectangle, if you had a "length" and "width" the perimeter would be:
"length" + "width" + "length" + "width"
or
2("length" + "width")
.
Area would be:
(length)(width)
.
So, if:
L = length
the
width = (100-2L)/2 = 50-L
.
Therefore, if A=Area then
A = L(50-L)
A = 50L-L^2
or
A = -L^2+50L