Sorry if this doesn't come out right- figuring out how to state it is part of my problem.(adsbygoogle = window.adsbygoogle || []).push({});

Let P be the set of all 3-tuples (a, b, c) in N such that a^{2}+ b^{2}= c^{2}and a < b.

Let Q be the set of all 3-tuples (x, y, z) in N such that x = m(2n + 1), y = m(2n^{2}+ 2n), and z = m(2n^{2}+ 2n + 1) for some m and n in N.

I want to figure out if P = Q. I know that for all sets S and T, (S = T) is equivalent to (S is a subset of T and T is a subset of S), but I don't know where to begin. Should I try to prove that for all 3-tuples t in N, if t is in P, then t is in Q and if t is in Q, then t is in P? Should I state it a different way (I tried, but it seemed more complicated)?

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# Proving two sets are equal

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