Question

Plz i need help and plz explain

Answer 1

`\frac{ {x}^(2) - 7x + 12}{ {x}^(2) - x - 12 } \\ = \frac{ {x}^(2) - 4x - 3x + 12 }{ {x}^(2) - 4x + 3x - 12 } \\ = (x(x - 4) - 3(x - 4))/(x(x - 4) + 3(x - 4)) \\ = ((x - 3)(x - 4))/((x + 3)(x - 4)) \\ = (x - 3)/(x + 3)`

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)