SOLUTION: a rectangle has a length that is 6ft less than twice the width. the aera is 80 squarre feet what are the dimensions of the rectangle

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Question 956718: a rectangle has a length that is 6ft less than twice the width. the aera is 80 squarre feet what are the dimensions of the rectangle
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
W=width; L=length=2W-6ft; A=Area
LW=A Substitute for L.
%282W-6ft%29%28W%29=80ft%5E2
2W%5E2-6Wft=80ft%5E2 Subtract 80 sq ft from each side.
2W%5E2-6Wft-80ft%5E2=0
2%28W%5E2-3Wft-40ft%29%5E2=0
2%28W-8%29%28W%2B5%29=0
W-8=0 or W+5=0
W=8 or W=-5 ANSWER 1: The width is 8 feet.
L=2W-6ft=2(8ft)-6ft=16ft-6ft=10ft ANSWER 2: The length is 10 feet.
CHECK:
LW=A
%2810ft%29%288ft%29=80ft%5E2
80ft%5E2=80ft%5E2