Here is the question: How would you convince someone that for integers a and b, a-b and b-a are opposites of each other? Here is my answer: a+(-a)=0 b+(-b)=0 because opposite of a = -a and opposite of b=-b now: (b-a)+(a-b)=o . So they are opposite. Is this correct.

Showing that adding the two terms results in 0 does indeed prove that the two terms are additive opposites.