If open paren x minus 5 close paren is a factor of f of x , which of the following must be true?

By the factor theorem, if (x − 5) is a factor of f(x), then f(5) = 0. Therefore, x = 5 is a root of f(x), which matches choice A. The factor does not require x = −5 to be a root.

AI-written and checked against the verified answer.