Whats up with the hacks?

Just played A match against a Tryndemere and i know from playing him that his ult lasts only 5 seconds and i know his damage output that he can do. In this match he would use his ult and it would last anywhere from 7 seconds to 20 seconds, yes i began counting. Not only would his ult last through the whole team fight, which normally lasted about 15 seconds, he would get a penta kill each team fight and would 2-3 hit the whole team even in the early game. Why should I, or anyone, play a game where the fun and competitiveness is taken away because of a hacker? Its not fair to the players that actually play the game.