1. The problem statement, all variables and given/known data This is a question from the book I'm studying called 'Mathematical Proofs: A transition to advanced mathematics' 2. Relevant equations Let a, b, n be integers, with n≥2. Prove that if a[itex]\equiv[/itex]b(mod n), then a2[itex]\equiv[/itex]b2(mod n). 3. The attempt at a solution Following the examples I assumed that I'd start by stating that since a[itex]\equiv[/itex]b(mod n), then a-b=nx... but from this point I'm stuck. Any help much appreciated.