Precalculus word problem

Question

If there are x teams in a sports league, and all the teams play each other twice, a total of N(x) games are played, where N(x)=x^2-x. A tiddly winks league has 10 teams, each of which play the others twice. If the league pays $30 per game, how much will it cost to play the entire schedule?

Answer 1

N(10) = (10)^2 - 10 = 100 - 10 = 90

90*30 = 270