Question 869013
First, the equation can be simplified:

{{{(1/3)(3x^2-6x-9)=(1/3)*0}}}
{{{x^2-2x-3=0}}}


Then, the term to use for Completing the Square is {{{(-2/2)^2=1}}}.


{{{x^2-2x+1-1-3=0}}}
{{{(x^2-2x+1)-1-3=0}}}
{{{(x-1)^2-4=0}}}
You can finish this for x.


Study this: <a href="http://www.algebra.com/tutors/Completing-the-Square-to-Solve-General-Quadratic-Equation.lesson?content_action=show_dev">Completing the Square to Solve General Quadratic Equation </a>