As per the definition of a hedge:

[quote]

To hedge a bet, to bet upon both sides; that is, after
      having bet on one side, to bet also on the other, thus
      guarding against loss.[/quote]

The question arises, and it comes with great validity. When is it a good time to hedge a bet? For one, and this happend frequently, when one plays a parlay, and all the games win, except the last one, which is pending. Fantastic way to clear some extra money, barring that the parlay will yield postive results. 

Playing the other side on the money line, will yield