SOLUTION: The width of a rectangle is 5 less than twice its length. If the area of the rectangle is 140 cm, what is the length of the diagonal?

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Question 311835: The width of a rectangle is 5 less than twice its length. If the area of the rectangle is 140 cm, what is the length of the diagonal?
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
W=2L-5
A=LW
140=L(2L-5)
140=2L^2-5L
2L^2-5L-140=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
X=(5+-SQRT(-5^2-4*2*-140])/2*2
X=(5+-SQRT(25+1,120])/4
X=(5+-SQRT1,145)/4
X=(5+-33.8378)/4
X=(5+33.8378)/4
X=38.8378/4
X=9.7 ANS.
X=(5-33.8378)/4
X=-28.8378/4
X=-7.21 ANS.