SOLUTION: if the area of the rectangle is 42in squared, find the value of x L=x-8 W=x-3

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Question 1115765: if the area of the rectangle is 42in squared, find the value of x
L=x-8
W=x-3
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
if the area of the rectangle is 42 in squared, find the value of x
L=x%2B8+->corrected
W=x-3
A=L%2AW
42=%28x%2B8%29%2A%28x-3%29
42=x%5E2-3x+%2B8x-24
0=x%5E2%2B5x-24-42
x%5E2%2B5x-66=0
x%5E2%2B11x-6x-66=0
%28x%5E2%2B11x%29-%286x%2B66%29=0
x%28x%2B11%29-6%28x%2B11%29=0
%28x+-+6%29+%28x+%2B+11%29+=+0

solutions:
x+-+6%29++=+0->x=6
(+%28x+%2B+11%29+=+0->x=-11 since we are looking for length and width, disregard negative solution

so, your solution is: highlight%28x+=+6%29

L=x%2B8+->L=6%2B8+->highlight%28L=14%29+
W=x-3->W=6-3->highlight%28W=3%29