SOLUTION: Solve by completing the square. Show your work. x^2+8x=9

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: Solve by completing the square. Show your work. x^2+8x=9      Log On


   

Question 297145: Solve by completing the square. Show your work.
x^2+8x=9
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B8x=9
Take (1/2) the x coefficient, square it, add it to both sides.
x%5E2%2B8x%2B16=9%2B16
%28x%2B4%29%5E2=25
Take the sqaure root of both sides,
x%2B4=0+%2B-+5
x=-4+%2B-+5
x=-9 and x=-1