SOLUTION: If a rectangle has the sides measuring (x+2)(2x+1) and the area is 252. Find the value of x.

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Question 804502: If a rectangle has the sides measuring (x+2)(2x+1) and the area is 252. Find the value of x.
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

%28x%2B2%29%282x%2B1%29+=+252
2x%5E2%2Bx%2B4x%2B2+=+252
2x%5E2%2B5x%2B2-252=0
2x%5E2%2B5x+-250=0
2x%5E2%2B25x-20x-250......group
%282x%5E2-20x%29%2B%2825x-250%29
2x%28x-10%29%2B25%28x-10%29
%28x-10%29%282x%2B25%29+=+0
solutions:
if %28x-10%29+=+0 => x=10
if +%282x%2B25%29+=+0=>x=-25%2F2=-12.5
since x represents the side of a rectangle, we need only positive solution; so, x=10