Question 835699
Use synthetic division.  If a nonzero remainder, this means {{{f(-3)=theNonZeroRemainder}}}.  If remainder is zero, then x+3 is a factor of f(x).



Checking  -3 as possible zero.


-3____|_____3____0_____-27____1_____0_____0_____-5
______|
______|__________-9____27_____0____-3_____9_____-27
___________3____-9______0_____1____-3_____9_____{{{highlight(highlight(-32))}}}



The remainder is -32, so this means, x+3 is NOT a factor of f, but that {{{highlight(f(-3)=-32)}}}.