Find all values of the variable for which the rational expression is undefined.
-$\frac{x^{2}-16}{x^{2}-3 x-40}$

A) $-8,5$
B) 0
C) $-4,4$
D) $-5,8$

Question

Find all values of the variable for which the rational expression is undefined.
-$\frac{x^{2}-16}{x^{2}-3 x-40}$

A) $-8,5$
B) 0
C) $-4,4$
D) $-5,8$

Quizplus · Accepted Answer

The rational expression is undefined when the denominator is zero. Factoring the denominator $x^2 - 3x - 40$ gives $(x - 8)(x + 5)$. Setting each factor to zero, we find the values $x = 8$ and $x = -5$ make the expression undefined.

Find All Values of the Variable for Which the Rational x2−16x2−3x−40\frac{x^{2}-16}{x^{2}-3 x-40}x2−3x−40x2−16​

Find All Values of the Variable for Which the Rational $\frac{x^{2}-16}{x^{2}-3 x-40}$