a is congruent to b modulo m denoted as a≡b(modn), if a and b have the remainder when they are divided by n, for a,b∈Z. Two integers a ...a is congruent to b modulo m denoted as a≡b(modn), if a and b have the remainder when they are divided by n, for a,b∈Z. Two integers a and b are said to be congruent modulo n, a≡b(modn), if all of the following are true: Proof: Let a,b∈Z such that a≡b (mod n). Proof: Let a,b,c∈Z, such that a≡b(modn) and b≡c(modn).