SOLUTION: The area of a rectangle is given by A = x2 – 2x + 30. Find the value of x if the total area of the rectangle is equal to 45 square units.

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Question 655010: The area of a rectangle is given by A = x2 – 2x + 30. Find the value of x if the total area of the rectangle is equal to 45 square units.
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
The area of a rectangle is given by A = x2 – 2x + 30. Find the value of x if the total area of the rectangle is equal to 45 square units.
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A+=+x%5E2+%96+2x+%2B+30
since they give A as 45, substitute it in:
45+=+x%5E2+%96+2x+%2B+30
0+=+x%5E2+%96+2x+%2B+15
factoring:
0+=+%28x%2B3%29%28x-5%29
x = {-3, 5}
throw out the negative solution (extraneous) leaving:
x = 5