Question 155724
The width of a rectangle is 4ft. less than the length. The area is 5ft^2. Find the length and the width.
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Let x = length of rectangle
then because "width of a rectangle is 4ft. less than the length" we get:
x-4 = width of rectangle
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Now, we also should know that the area of any rectangle is:
length * width
Therefore, we get out equation:
x(x-4) = 5
x^2 -4x = 5
x^2 -4x - 5 = 0
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Factoring we get: 
(x-5)(x+1) = 0
x = {-1, 5}
Since we can't have a negative length the answer must be:
x = 5 feet (length)
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Previously, we said:
x-4 = width of rectangle
x-4 = 5-4 = 1 feet (width)