SOLUTION: Solve by completing the square. x^2-18x=-106

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Question 308462: Solve by completing the square.
x^2-18x=-106
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by completing the square.
x^2 - 18x = -106
:
x^2 - 18x + ___ = -106
Find the third term to complete the square: using the coefficient of x: (18/2)^2 = 81
Add 81 to both sides
x^2 - 18x + 81 = -106 + 81
:
x^2 - 18x = 81 = -25
:
(x - 9)^2 = -25
:
Find the square root of both sides
x - 9 = +/-sqrt%28-25%29
using i
x - 9 = +/- 5i
two solutions
x = 9 + 5i
and
x = 9 - 5i