5. A and B are competing in an archery match. In each round, the winner gets 7 points, the loser loses 2 points, and in the case of a tie, both get 2 points. After 10 rounds, the total score of both players is 43 points. Therefore, there were $(\quad$ ) rounds that ended in a tie.
【Analysis】In sports matches, the total score increases by $7-2=5$ (points) when there is a win or loss, and by $2+2=4$ (points) in a draw. In 10 games, the total score is 43 points, which can be solved using the chicken and rabbit in the same cage problem, leading to 7 draws.