SOLUTION: The length of a rectangle is 1ft less than twice its width, and the area of the rectangle is 36ft^2 . Find the dimensions of the rectangle.

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Question 426018: The length of a rectangle is 1ft less than twice its width, and the area of the rectangle is 36ft^2 . Find the dimensions of the rectangle.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let W = width
Let L = length
given:
(1) +W%2AL+=+36+ ft2
(2) +L+=+2W+-+1+ ft
-----------------
From (1):
(1)
Multiply both sides by W
+36+=+2w%5E2+-+W+
+2W%5E2+-+W+-+36+=+0+
Use quadratic equation:
W+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a+=+2
b+=+-1
c+=+-36
W+=+%28-%28-1%29+%2B-+sqrt%28+%28-1%29%5E2-4%2A2%2A%28-36%29+%29%29%2F%282%2A2%29+
W+=+%28+1+%2B-+sqrt%28+1%2B+288+%29%29%2F+4+
+W+=+%281+%2B+17%29%2F4+
+W+=+9%2F2+
W+=+4.5+
and
+L+=+2W+-+1+
+L+=+9+-+1+
+L+=+8+
The dimensions are 4.5 ft x 8 ft