SOLUTION: the length of a rectangle is 8 meters less than twice its width. if the diagonal of the rectangle is 20 meters find the length and width

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Question 115868:
the length of a rectangle is 8 meters less than twice its width. if the diagonal of the rectangle is 20 meters find the length and width

Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
L=2W-8
A^2+B^2=C^2
(2W-8)^2+W^2=20^2
4W^2-32W+64+W^2=400
5W^2-32W+64-400=0
5W^2-32W-336=0
(5W+28)(W-12)=0
W-12=0
W=12 ANSWER FOR THE WIDTH.
L=2*12-8
L=24-8
L=16 ANSWER FOR THE LENGTH.
PROOF
12^2+16^2=20^2
144+256=400
400=400