Question

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

Answer 1

Answer:

A. (x - (7 + i))

Step-by-step explanation:

Answer 2

Hello from MrBillDoesMath!

Answer:

x + 9 and (x + ( i - 7)) are factors

Discussion:

If f(x) has roots -9 and 7-i then

f(x) = g(x)(x - (-9))  (x - (7-i))            ( g(x) is a polynomial of degree less than f(x))

That is, x + 9 and (x + ( i - 7)) are factors of f(x)

BTW: if the coefficients of f(x) are real (not stated in the Question) then the conjugate of 7-i, i.e. 7 + i, is  also be a root.

Thank you,

MrB