SOLUTION: x(x-8)=-5

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Question 748925: x(x-8)=-5
Answer by LyokoJames(2) About Me  (Show Source):
You can put this solution on YOUR website!
x(x-8)=-5
We will solve this by completing the square
First, distribute the x into (x-8)
x%5E2-8x+=+-5
Then move the -5 over to the left side by adding 5 to both sides
x%5E2-8x%2B5+=+0
Rewrite x%5E2-8x as %28x%2B4%29%5E2+-+16 so you have:
%28x%2B4%29%5E2-16%2B5+=+0 which simplifies to:
%28x%2B4%29%5E2-11=0
Move the -11 over by adding 11 to both sides
%28x%2B4%29%5E2=11
Now that we have completed the square we can take the square root of both sides:
x%2B4=0+%2B-+sqrt%2811%29
Bring the 4 over by subtracting 4 from both sides
x=-4%2B-sqrt%2811%29
So x=+-4%2Bsqrt%2811%29+or+x+=+-4-sqrt%2811%29}