[tex] \frac{ {x}^{2} - 7x + 12}{ {x}^{2} - x - 12 } \\ = \frac{ {x}^{2} - 4x - 3x + 12 }{ {x}^{2} - 4x + 3x - 12 } \\ = \frac{x(x - 4) - 3(x - 4)}{x(x - 4) + 3(x - 4)} \\ = \frac{(x - 3)(x - 4)}{(x + 3)(x - 4)} \\ = \frac{x - 3}{x + 3} [/tex]
x² - x - 12 ≠ 0
x² - 4x + 3x - 12 ≠ 0
x (x - 4) + 3 (x - 4) ≠ 0
(x + 3)(x - 4) ≠ 0
x ≠ -3 or x ≠ 4
(B)
