Question 312854: the length of a rectangle is 5 ft more than twice its width, and the area of the rectangle is 88ft squared. Find dimensions
Answer by rapaljer(4671)   (Show Source):
You can put this solution on YOUR website! Let x = the width
2x+5= the length
The equation is A=L*W
x(2x+5)=88
2x^2+5x-88=0
I hope this factors:
(2x-11)(x+8)=0
There appear to be two solutions:
2x-11=0 or x+8=0
2x=11 or x=-8 This answer is rejected since a side of a rectangle can't be negative.
x=11/2 or 5.5 ft = width
2x+5=Length
2(11/2)+5=11+5=16 = Length
Check: Area = L*W = 16*5.5 = 88sq ft.
It checks.
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