SOLUTION: The length of rectangle is three times its width, with a perimeter of 80 cm, solve for the rectangles area.

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Question 883096: The length of rectangle is three times its width, with a perimeter of 80 cm, solve for the rectangles area.
Answer by JulietG(1812) About Me  (Show Source):
You can put this solution on YOUR website!
2L + 2W = P
2L + 2W = 80
L = 3W
Substitute the known value of L from the last equation into the first.
2(3W) + 2W = 80
6W + 2W = 80
8W = 80
Divide each side by 8
W = 10
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If the width is 10, then the length is 3x that, or 30
Area = length * width
A = 10 * 30
Area = 300 square cm