Answer
$x-3$ and $x+3$ are both factors of P(x) since when P(x) is divided by each one, the remainder is 0.
(refer to the step by step part for the solution)
Work Step by Step
RECALL:
The factor theorem states that c is a zero of P if and only if x−c is a factor of P(x).
$c=3$ therefore $x-c = x-3$
$c=-3$ therefore $x-c = x-(-3)=x+3$
Divide P(x) by $x-3$, and by $x-3$ using synthetic division to have: