if a polynomial function f(x) has roots -9 and 7-i, what must be a factor of f(x)?

Answer:
[tex](x-(7+i))[/tex] is the answer
Step-by-step explanation:
a polynomial function f(x) has roots -9 and 7-i
Polynomial roots always come with conjugate pairs
7-i is one of the root
7+i is the another root
So we have three roots
If 'a' is a root then (x-a) is a factor
-9 is one of the root , factor is (x+9)
7-i is a root then factor is [tex](x-(7-i))[/tex]
7+i is a root then factor is [tex](x-(7+i))[/tex]
[tex](x-(7+i))[/tex] is the answer