Just addressing a part of the question that the other answers did not.
Is the comment actually deleted, or do I just have no permissions to see it?
Yes, your comment was actually deleted.
If it was deleted, can I see the reason why somewhere?
I don't know of any way to track comment deletions, no. As far as I'm aware, they are obliterated. I would guess the only way to know for sure would be to ask the moderator who confirmed the flag (or saw it naturally and deleted it) - but good luck figuring out who that was. In this case, the reason should be obvious anyway: the question is not constructive. How does asking someone if the question is homework help anyone or change anything?
As another answer stated, if you think it is homework and you don't want to help someone with their homework, don't answer. Personally, I feel a lot more taken advantage of when people struggle with simple concepts they're paid for, and ask for help here that helps them get paid at their job, than when students ask for help in passing some course - which they may never use in their career - because they partied too late or because their instructor sucks. (Sometimes they're just lazy students, but <shrug>).