This is an inequality. Change the < sign to an = sign and solve the equation.
You can simplify 2log base2 (x) by moving the 2 inside the logarithm.
Log base 2 (6-x) = log2 (x^2)
For the equation to be equal the argument of the logarithm on both sides of the equation must also be equal.
6-x = x^2
Solve for X.
X = 2, -3
I hope that helps.