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Now we will transition into discussing some simple properties that congruences have. We begin by defining the idea that x relates to y if a relationship between inputs x and output y exists. (Functions, as you may recall from basic algebra, are a special kind of relation in which our input x has at most one output y.) We can define the relation for congruences like so: for integers a, b, and n with n > 0, a relates to b if a is congruent to b mod n.

We can now use this relation to define three congruence properties, the first of which is the reflexive property. The reflexive property states that a relates to a, or that a is congruent to a mod n for integers a and n with n > 0. To see this, we use the definition of congruence to write out that n divides a - a, or 0. This is always true since 0 divides every integer excluding 0, which n cannot be. Therefore, congruence is a reflexive relation. We can use Python to verify the reflexive property for congruences quite easily.

### Instructions

1.

Print whether or not this congruence (satisfying the conditions for the reflexive property) is, indeed, true:

$5 \equiv 5\;(mod\;3)$