Question

If a polynomial function f(x) has roots -9 and 7 -i, which must be a factor of f(x)

Answer 1

(x + 9) (x - 7)

Explanation:

when we put x + 9 = 0 then x = -9 as it's the root of the fuction.

same thing here: x - 7 = 0 then x = 7