Arelation r on a set x is an equivalence relation if r is reflexive, symmetric, and transitive. fix an integer m ≥ 2 . show that the relation defined on the set z of integers by a r b ( a , b ∈ z ) if and only if a ≡ b ( mod m ) is an equivalence relation. (recall that a ≡ b ( mod m ) means that when dividing a by m and b by m you get the same remainder.)