SOLUTION: The length of a rectangle is three times its width. If the perimeter of the rectangle is 40m , find its area

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Question 412852: The length of a rectangle is three times its width.
If the perimeter of the rectangle is 40m , find its area
Answer by rfadrogane(214) About Me  (Show Source):
You can put this solution on YOUR website!
The length of a rectangle is three times its width.
If the perimeter of the rectangle is 40m , find its area.
Sol'n:
let w-width of the rectangle
l-length of the rectangle
l=3w ---(1)
P=2l+2w=40
l+w=20 ---(2)
substitute: (1)into(2)
3w+w=20
4w=20
w=5 m
l=15 m
For area:
A=lw
A=5(15)
A=75 m^2 ---answer
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