What is the domain function f (x) = * - 5 over x^2 - 9

A. all real number but 9

B. all real numbers but 3 and - 3

C. all positive real numbers

D. all real numbers but 5 and 9

Assuming your function looks like this: (x-5) / (x^2 - 9), the numbers that are not "allowed" are the ones that cause the denominator to equal 0. That would be a 3 and a - 3, because when you square a 3 and a - 3, your result is a 9, and putting a 9 in there makes that denominator 0. So your answer is b