Final answer:
Beowulf wins the battle by positioning himself strategically and seizing the right opportunity to defeat the enemy.
Step-by-step explanation:
Beowulf wins the battle by putting himself in a position where defeat is impossible and seizing the moment to defeat the enemy. This can be seen in line 496-500 of the text. Beowulf's skill as a fighter allows him to anticipate the enemy's moves and make calculated decisions to ensure victory.