SOLUTION: How do I complete a square?

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Question 823356: How do I complete a square?
Answer by erica65404(394) About Me  (Show Source):
You can put this solution on YOUR website!
You usually are given the equation ax%5E2%2Bbx%2Bc=0.
The first thing you do is take half of b and square it %28b%2F2%29%5E2. Then you add this to both sides. ax%5E2%2Bbx%2Bc%2B%28b%2F2%29%5E2=%28b%2F2%29%5E2.
When you factor it you would get %28x%2B%28b%2F2%29%29%5E2%2Bc=%28b%2F2%29%5E2. Then you would move the %28b%2F2%29%5E2 to the left side.
%28x%2B%28b%2F2%29%29%5E2%2Bc-%28b%2F2%29%5E2=0

example:
x%5E2%2B8x%2B3=0
take half of 8 and square it, then add this number to both sides of the equation.
x%5E2%2B8x%2B16%2B3=16
This becomes %28x%2B4%29%5E2%2B3=16
Then move the 16 to the left side
%28x%2B4%29%5E2-13=0