These are pretty easy once you get the concept.
think of random letter (x) as the term y, so in the case of p(x)=-3+4x, its just asking what is y when x equals all those values.
so p(-2) = -3 + 4(-2), since its asking to plug in -2 for x, which equals -11
p(0) = -3 + 4(0)
= -3
p(5) = -3 + 4(5)
= 17