[tex] - 6x(x + 12) - 15(x + 12 = 0) \\ \\ 1. \: - 6x^{2} - 87x - 180 = 0 \\ \\ 2. \: - 3(2x + 5)(x + 12) = 0 \\ \\ 3. \: 2x + 5 = 0 \: or \: x + 12 = 0 \\ \\ x = \frac{ - 5}{2} \: or \: x = - 12[/tex]
