You can put this solution on YOUR website! 64 = x² + 12x
x² + 12x - 64 = 0 {subtracted 64 from both sides}
(x + 16)(x - 4) = 0 {factored into two binomials}
x + 16 = 0 or x - 4 = 0 {set each factor equal to 0}
x = -16 or x = 4 {solved each equation for x}