SOLUTION: The length of a rectangle is 1 cm less than twice the width. The area is 45cm^2. what are the dimensions of the rectangle?

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Question 865056: The length of a rectangle is 1 cm less than twice the width. The area is 45cm^2. what are the dimensions of the rectangle?
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
L length
w width
L=-1+2w
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wL=45, given.
w%282w-1%29=45, substitution.
2w%5E2-w-45=0, combined steps simplification.
highlight%28w=%281%2Bsqrt%2891%29%29%2F4%29.
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Final forms based on general solution to a quadratic equation.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

The length of a rectangle is 1 cm less than twice the width. The area is 45cm^2. what are the dimensions of the rectangle?


Let width be W

Then length is 2W - 1

Area: W(2W - 1) = 45

2W%5E2+-+W+-+45+=+0

2W%5E2+-+10W+%2B+9W+-+45+=+0

2W%28W+-+5%29+%2B+9%28W+-+5%29+=+0

(W - 5)(2W + 9) = 0



W, or width = highlight_green%285%29         OR           2W = - 9 (ignore)

Length = 2(5) - 1, or highlight_green%289%29



You can do the check!! 



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