Answer:
r + 7 is a factor.
Step-by-step explanation:
You have to divide [tex]3r^{4} +23r^{3} +15r^{2} +r - 42[/tex] by r + 7. If the remainder is 0, then r + 7 is a factor of [tex]3r^{4} +23r^{3} +15r^{2} +r - 42[/tex].
I did that and the remainder was 0.
So, yes, r + 7 is a factor.
You will need to learn how to do that division in order to solve this problem. OK?
