Question 1031482
I assume by a prime polynomial you mean "factorable over the integers."


16y^2 - 49 is factorable since it is the difference of two squares, and can be written as (4y-7)(4y+7). But 49y^2 + 16 can't be factored over integers.


In general, determining whether a polynomial is factorable over integers is difficult, but sometimes you may be able to look for patterns, or find roots of the polynomial, etc.