SOLUTION: How do you solve by completing the square? The problem is x^2+6x+1=0 Thank you

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Question 152941This question is from textbook Intermediate Algebra
: How do you solve by completing the square?
The problem is x^2+6x+1=0
Thank you This question is from textbook Intermediate Algebra

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x by completing the square:
x%5E2%2B6x%2B1+=+0 First, subtract 1 from both sides.
x%5E2%2B6x+=+-1 Now complete the square in x by adding the square of half the x-coefficient to both sides. This is :%286%2F2%29%5E2+=+9
x%5E2%2B6x%2B9+=+-1%2B9 Simplify the right side.
x%5E2%2B6x%2B9+=+8 Factor the left side.
%28x%2B3%29%5E2+=+8 Now take the square root of both sides.
x%2B3+=+0%2B-sqrt%288%29 N.B. The zero on the right side is an artifact added so that I could show the + or - symbols. Finally, subtract 3 from both sides
x+=+-3%2Bsqrt%288%29 or x+=+-3-sqrt%288%29 This can be further simplifed to:
x+=+-3%2B2sqrt%282%29 or x+=+-3-2sqrt%282%29