Do what? If you mean to find when it equals zero...
By inspection you can see that if x=0 or 2 the expression is equal to zero...
You multiply each term in the parentheses by the term outside the parentheses...like:
3x*3x+3x*6 which is equal to:
9x^2+18x If you meant to expand it....
9x(x+2) If you meant to factor it completely