Answer:
a) 9/7
Step-by-step explanation:
[tex] \dfrac{x^2 + x - 20}{x^2 - x - 12} = [/tex]
[tex] = \dfrac{(x + 5)(x - 4)}{(x + 3)(x - 4)} [/tex]
[tex] = \dfrac{x + 5}{x + 3} [/tex]
x = 4
[tex] = \dfrac{4 + 5}{4 + 3} [/tex]
[tex] = \dfrac{9}{7} [/tex]
