SOLUTION: The length of a rectangle is five less than four times the width. If the area is 9ft^2, what are the dimensions of the rectangle? Write and equation to model situation

Algebra ->  Surface-area -> SOLUTION: The length of a rectangle is five less than four times the width. If the area is 9ft^2, what are the dimensions of the rectangle? Write and equation to model situation      Log On


   

Question 1095490: The length of a rectangle is five less than four times the width. If the area is 9ft^2, what are the dimensions of the rectangle? Write and equation to model situation
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Dimensions are 4w-5 and w.

You can model the area just based on the width, w.
highlight%28w%284w-5%29=9%29
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4w%5E2-5w-9=0
discr, 25%2B16%2A9=169=13%5E2
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w=%285%2B-+13%29%2F8
w=%285%2B13%29%2F8=18%2F8
w=9%2F4
highlight%28w=2%261%2F4%29
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highlight%28length=4%29