Question

every integer is a rational number...?​

Answer 1

Every integer is a rational number, since each integer can be written in the form p/q.

Answer 2

Sure they are

Every integer is a rational number because they could be written in form of $\frac{p}{q}$ where $q ≠ 0$. We can say that every integer, maybe positive or negative, can be written in this format and even 0 too.