Solve LaTeX:  \displaystyle 12 x^{2} + x - 6=0

This is an ac method factoring. The factors of LaTeX:  \displaystyle ac = -72 that add up to LaTeX:  \displaystyle 1 are LaTeX:  \displaystyle -8 and LaTeX:  \displaystyle 9 . Separating gives LaTeX:  \displaystyle (12 x^{2} - 8 x)+(9 x - 6)=0 . This gives LaTeX:  \displaystyle (4 x + 3)(3 x - 2)=0 . The solutions are LaTeX:  \displaystyle x = - \frac{3}{4} and LaTeX:  \displaystyle x = \frac{2}{3}