Question

Given a polynomial f(x), if (x + 3) is a factor, what else must be true?

Answer 1

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The best and most correct answer among the choices provided by the question is f(-3) = 0.       
    
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Answer 2

Answer:

$f(-3)=0$

Step-by-step explanation:

we know that

The zero of a function is the value of x when the value of the function is equal to zero

In this problem

If $(x+3)$ is a factor of a polynomial

then

$x=-3$ is a zero of the polynomial

so

For $x=-3$ -------> $f(-3)=0$