I am still having troulbe with these. Her is another one I am stuck on. I think the prime is getting me.

Factor completely or state that it is prime

x^2 + 9xy + 16y^2

The factors of 16 are:
16 x 1.
8 x 2.
4 x 4.
None of these add together to give 9 so it can't be factored as is. Did you make a typo? Is the 9 a 10 or an 8. It would work then.

Does this mean it is prime? No typo

I don't know your definition of prime but the equation, as is, can't be factored.