Question

Please hurry I’m being timed! (50 pts)

For which rational
expression is -2 an excluded value of x?
A) x-3/x^2-4
B) x-3/x^2+4
C) x^2-4/x-3
D) x^2+4/x-3

Answer 1

Option A) is the answer

Answer 2

A

Explanation:

An excluded value is any value of x that makes the denominator of the rational expression zero as this would make the expression undefined.

For expression A

`(x-3)/(x^2-4)`

The denominator will be zero when x² - 4 = 0

x² - 4 is a difference of squares, thus

(x - 2)(x + 2) = 0

x - 2 = 0 ⇒ x = 2

x + 2 = 0 ⇒ x = - 2

The excluded values of x are x = ± 2 ⇒ A