Question

a congruent b mod n , a+c congruent b+c (mod n) for​

Answer 1

Answer:

If a and b are integers and n > 0, we write a ≡ b mod n to mean n|(b − a). We read this as “a is congruent to b modulo (or mod) n. For example, 29 ≡ 8 mod 7, and 60 ≡ 0 mod 15. The notation is used because the properties of congruence “≡” are very similar to the properties of equality “=”.