/sci/ - Science & Math

I'm working on teaching myself set theory with a free textbook and the part on equivalence relations is very short and I'm still a little confused.

Unfortunately it only gives solutions to odd problems, and even those I'm a little unsure of. But here, for this one:

If I understand it right, an equivalence class a is the set of all Xs such that xRa, and two are equal if their Xs match.

So here, if I'm doing it right, is the set R = {(a,a), (b,b), (c,c), (d,d) (e,e), (a,d), (b,c), (e,a), (c,e)}?

If so, how do I get the equivalence classes from that?