SOLUTION: solve the equation by completing the square x^2-12x=5 show work step by step; also (x-3)^2=36

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Question 408306: solve the equation by completing the square
x^2-12x=5 show work step by step;
also
(x-3)^2=36
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
1. For the quadratic x%5E2+-+12x+=+5, add 36 to both sides to obtain

x%5E2+-+12x+%2B+36+=+41 Factor:

%28x-6%29%5E2+=+41 --> x-6+=+sqrt%2841%29 or x-6+=+-sqrt%2841%29. From here it follows that x+=+6+%2B-+sqrt%2841%29.

2. The equation %28x-3%29%5E2+=+36 does not need any square completion, we can simply take the square root of both sides (note that the negative square root can still count) to get x-3+=+6, x-3+=+-6 --> x+=+9 or x+=+-3.