Solve LaTeX:  \displaystyle - 3 x^{2} - 9 x + 12=0

Since the GCF is LaTeX:  \displaystyle -3 we need we factor out the GCF to get LaTeX:  \displaystyle -3(x^{2} + 3 x - 4) . This is now a pq method factoring. The factors of LaTeX:  \displaystyle -4 that add up to LaTeX:  \displaystyle 3 are LaTeX:  \displaystyle -1 and LaTeX:  \displaystyle 4 . This gives LaTeX:  \displaystyle -3(x - 1)(x + 4)=0 . The solutions are LaTeX:  \displaystyle x = 1 and LaTeX:  \displaystyle x = -4