SOLUTION: A rectangle's length, l, is 5 times the width, w. If the area of the rectangle is 80 cm2, what are the dimensions of the rectangle?

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Question 522495: A rectangle's length, l, is 5 times the width, w. If the area of the rectangle is 80 cm2, what are the dimensions of the rectangle?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Start with the formula for the area of a rectangle:
A+=+l%2Aw Substitute l+=+5w and A+=+80
80+=+%285w%29%2Aw Simplify.
80+=+5w%5E2 Divide by 5.
16+=+w%5E2 Take the square root.
4+=+w and...
l+=+5%284%29
l+=+20
The dimensions are:
Length = 20cm. and width = 4cm.