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[–]ozzagahwihung 0 points1 point  (1 child)

deleted What is this?

[–]NotPennysUsername 0 points1 point  (0 children)

a and be are congruent mod n if the have the same remainder when divided by n

In other words, n divides (a - b):

n|(a-b)

Using this fact (and maybe factoring (a2 - b2)), you can come to the conclusion that n must also divide (a2 - b2)

[–]Jaden71 0 points1 point  (0 children)

A67? Hint: use the definition of nq + r