SOLUTION: The area of a rectangle is 15 square feet. The width can be represented by x - 3.5 and the length by 'x'. What are the dimensions of the rectangle? I've tried this problem a doz

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Question 380097: The area of a rectangle is 15 square feet. The width can be represented by x - 3.5 and the length by 'x'. What are the dimensions of the rectangle?
I've tried this problem a dozen times. I don't know what it is I'm doing wrong.

Found 2 solutions by richard1234, mananth:
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
The area is just (x)(x - 3.5) = 15 -->
x%5E2+-+3.5x+-+15+=+0
2x%5E2+-+7x+-+30+=+0
%282x+%2B+5%29%28x+-+6%29+=+0
x = -5/2 or x = 6. We take the positive value x = 6 and check: 6(6 - 3.5) = 15.

Answer by mananth(16949) About Me  (Show Source):
You can put this solution on YOUR website!
wid th = x-3.5
length =x
..
Area = l*w
x(x-3.5)=15
x^2-3.5x=15
multiply by 2
2x^2-7x=30
-30
2x^2-7x-30=0
2x^2-12x+5x-30=0
2x(x-6)+5(x-6)=0
(2x+5)(x-6)=0
x= 6 feet, the length
x-3.5
=6-3.5 = 2.5 feet, the width.
...
CHECK
Area = l*w
6*2.5 = 15
..
m.ananth@hotmail.ca
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