SOLUTION: The formula x^2-x=N can used to determine the total number of games played, N, in a league of X teams in which all teams play each other twice. Serena referees for a soccer league

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: The formula x^2-x=N can used to determine the total number of games played, N, in a league of X teams in which all teams play each other twice. Serena referees for a soccer league      Log On


   

Question 207206This question is from textbook
: The formula x^2-x=N can used to determine the total number of games played, N, in a league of X teams in which all teams play each other twice. Serena referees for a soccer league in which all teams play each other twice and a total of 90 games is played. How many teams are in the league? This question is from textbook

Answer by jringelman(2) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-x=90
x(x-1)=90
x(x-1)=10*9
x(x-1)=10(10-1)
therefore, x=10 (there are 10 teams in the league)