SOLUTION: the area of the rectangle below is 40. WHat is the perimeter Width: x+3 Length: x+6

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Question 293217: the area of the rectangle below is 40. WHat is the perimeter
Width: x+3
Length: x+6
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
The area of a rectangle is given by:
A+=+L%2AW Substitute L+=+%28x%2B6%29, W+=+%28x%2B3%29, and A+=+40
40+=+%28x%2B6%29%28x%2B3%29 Perform the multiplication.
40+=+x%5E2%2B9x%2B18 Subtract 40 from both sides.
x%5E2%2B9x-22+=+0 Solve this quadratic equation by factoring.
%28x%2B11%29%28x-2%29+=+0 Apply the "zero product" rule.
x%2B11+=+0 or x-2+=+0 so that...
highlight%28x+=+-11%29 or highlight_green%28x+=+2%29 Discard the negative solution as the dimensions cannot be negative.
L+=+x%2B6 Substitute x = 2.
L+=+2%2B6
highlight_green%28L+=+8%29 and...
W+=+x%2B3 Substitute x = 2.
W+=+2%2B3
highlight_green%28W+=+5%29