Why won't my tablet charge?

So I had this tablet laying around the house, and no one was using it because we had lost the charger (and no one wanted to replace it) so I ordered a charger on amazon and I plugged my tablet in and waited for about 20 min before trying to turn it on. It isn't working. I do not think it has anything to do with the charger. Anyway, I would be really grateful if someone can tell me what to do!