SOLUTION:

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Question 297152:
Answer by drparpor(2)   (Show Source): You can put this solution on YOUR website!
Solve by completing the square. show your work.

x^2+8x=9
You take half the 8 and square it, which gives you 16 then you add the 16 to each side == > x^2 + 8x + 16 = 9 + 16
The equation becomes (x + 4)^2 = 25
take the sq root of each side then solve for x:
X + 4 = 5 =====> x = 1