SOLUTION: solve x^2+18=9x by completing the square.

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Question 195441: solve x^2+18=9x by completing the square.
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B18=9x
Move all the x's to the left:
x%5E2-9x%2B18=0
x%5E2-9x=+-18
Add to both sides half b coefficient then square it:
x%5E2-9x%2B%2881%2F4%29=+-18+%2B+%2881%2F4%29
%28x-%289%2F2%29%29%5E2=+-%2872%2F4%29+%2B+%2881%2F4%29
%28x-%289%2F2%29%29%5E2=+%289%2F4%29
Taking the square root of both sides:
x-%289%2F2%29=+3%2F2
x+=+3%2F2+%2B+%289%2F2%29
x+=+12%2F2
x+=+6