SOLUTION: Solve by completing the square: x^2 + 8x + 13 = 0

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Question 196540: Solve by completing the square:
x^2 + 8x + 13 = 0
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2+%2B+8x+%2B+13+=+0
x%5E2+%2B+8x+=+-13
x%5E2+%2B+8x+%2B+%288%2F2%29%5E2+=+-13+%2B+%288%2F2%29%5E2
x%5E2+%2B+8x+%2B+16+=+-13+%2B+16
The left side is a perfect square
%28x+%2B+4%29%5E2+=+3
Take the square root of both sides
x+%2B+4+=+sqrt%283%29
x+=+14+%2B+sqrt%283%29
and
x+%2B+4+=+-sqrt%283%29
x+=+-4+-+sqrt%283%29
I'll check the 2nd result
x%5E2+%2B+8x+%2B+13+=+0
%28-4+-+sqrt%283%29%29%5E2+%2B+8%2A%28-4+-sqrt%283%29%29+%2B+13+=+0
16+%2B+8%2Asqrt%283%29+%2B+3+-+32+-+8%2Asqrt%283%29+%2B+13+=+0
16+%2B+3+-+32+%2B+13+=+0
0+=+0
OK