The length of a rectangle is three times its width.If the perimeter is 80 feet, what are the dimensi

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The length of a rectangle is three times its width.If the perimeter is 80 feet, what are the dimensions?

We're given 2 equations:

1. l = 3w
2. P = 80 = 2l + 2w = 80

Substitute (1) into (2) for l:
2(3w) + 2w = 80
6w + 2w = 80
8w = 80

Divide each side by 8:
8w/8 = 80/8
w = 10

Substitute w = 10 into (1)
l = 3(10)
l = 30