Question

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 nequals=xsquared2minus−x. a chess league has 1515 teams. what is the total number of games to be played if each team plays every other team​ twice?

Answer 1

Given that 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

$n=x^2-x$

If a chess league has 15 teams the total number of games to be played if each team plays every other team​ twice is given by

$n=15^2-15 \\ \\ =225-15=210$