Question

If (x+k) is a favor of f(x) which of the following must be true?

A) f(k)=0
B) f(-k)=0
C) a root of f(x) is x=k
D) a y-intercept of f(x) is x=-k

Answer 1

B

Explanation:

A factor of f(x) has the form (x+k). We know to find the zeros or roots of the function we set the factors equal to 0.

So (x+k)=0 and solve for x. x=-k. This means f(-k)=0.