SOLUTION: the length of a rectangle is 4 centimeters less than twice its width. the perimeter of the rectangle is 64cm. what are the dimensions of the rectangle? Having trouble figuring out

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Question 595084: the length of a rectangle is 4 centimeters less than twice its width. the perimeter of the rectangle is 64cm. what are the dimensions of the rectangle? Having trouble figuring out this one. Thanks

Answer by llorton(14) About Me  (Show Source):
You can put this solution on YOUR website!
l = length of rectangle in centimeters
w = width of rectangle in centimeters
l = 2*w - 4 (The length is 4 cm less than twice its width.)
2*l + 2*w = 64 (The perimeter equals 64 cm. = 2*length + 2*width)
2*(2*w-4) + 2*w = 64
4*w - 8 + 2*w = 64
6*w -8 = 64
6*w - 8 + 8 = 64 + 8
6*w = 72
6*w/6 = 72/6
w = 12
l = 2*12 - 4 = 24 - 4 = 20
check: 2*12 + 2*20 = 24 + 40 = 64
The answers are length = 20 cm. and width = 12 cm.