If there are x teams in a league and each team plays every other team twice, then the total number of games (N) to be played is given by N=x2−x. A chess league has 13 t eams. What is the total number...

If there are x teams in a league and each team plays every other team twice, then the

total number of games (N) to be played is given by

N=x2−x.

A chess league has

13 t

eams. What

is the total number of games to be played if each team plays every other team twice?