SOLUTION: The length of a square with side x cm is increased by 3cm. If the area of the new square is 121 cm^2, what is X? This problem was asked for me to solve it by completing the squar

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Question 1082890: The length of a square with side x cm is increased by 3cm. If the area of the new square is 121 cm^2, what is X?
This problem was asked for me to solve it by completing the square but I'm completely stuck And don't know how to start to solve the problem.
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
If the area of the new square is 121 cm^2, what is x?
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x, original square
x+3, the new square

New square area, %28x%2B3%29%5E2=121
Solve for x.

x%5E2%2B6x%2B9=121
x%5E2%2B6x%2B9-121=0
x%5E2%2B6x-112=0, but this should not be necessary. Square expression is already complete at x%5E2%2B6x%2B9=121 or at %28x%2B3%29%5E2=121.

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Instead, no need to Complete Square.
Just use x%2B3=sqrt%28121%29=11
x=11-3
x=8