SOLUTION: if the length of a rectangle is 3 times its width and the perimeter is 56cm what is the area?

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Question 304847: if the length of a rectangle is 3 times its width and the perimeter is 56cm what is the area?
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
L=3W
P=2L+2W
56=2*3W+2W
56=6W+2W
8W=56
W=56/8
W=7 cm. ANS.
L=3*7=21 cm. ANS.
PROOF:
56=2*21+2*7
56=42+14
56=56
AREA=7*21=147 cm^2 ANS. FOR THE AREA.