q) is
true, we assume that p is true and use that to show that q must also be true.4. To prove that an if--then statement (p q) is
true, we assume that p is true and use that to show that q must also be true.
Proof Suppose that a = d + rm and b = d + sm for some integers d, r, and s.
We are trying to conclude that a + c = b + c + tm for some integer t. One equation which we might want to aim for is a = b + tm. Try to use the above two equations to show that a = b + tm.