Question 139545
You can do this one in several ways:


You could move the constant term to the other side by adding 6 to both sides, then take the square root.  Just remember to consider both the positive and negative roots.


You could use the quadratic formula with {{{a=1}}}, {{{b=0}}}, and {{{c=-6}}}.  Remember the quadratic formula is: {{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 


You could use the fact that {{{6=(sqrt(6))^2}}} and factor the quadratic using the difference of two squares factorization.  Then apply the Zero Product Rule.  Personnally, I like this method best because it won't allow you to forget to consider the negative root and it isn't as messy as the quadratic formula.