Question

For what values of x is the rational expression below undefined?

Answer 1

Answer:

B and D

Step-by-step explanation:

Given

$\frac{x+8}{x^2-2x-24}$

The denominator of the rational function cannot be zero as this would make it undefined. Equating the denominator to zero and solving gives the values that x cannot be.

Solve x² - 2x - 24 = 0, that is

(x - 6)(x + 4) = 0

Equate each factor to zero and solve for x

x - 6 = 0 ⇒ x = 6 → B

x + 4 = 0 ⇒ x = - 4 → D