M是AC的中点,所以AM = MC
N是BC的重点,所以BN = NC
MN = NC + CM
AB = AM + MC + CN + BN = 2NC + 2CM = 2MN
所以
1、MN = 15/2厘米
2、AB = 12厘米
3、AB = 2MN
M是AC的中点,所以AM = MC
N是BC的重点,所以BN = NC
MN = NC + CM
AB = AM + MC + CN + BN = 2NC + 2CM = 2MN
所以
1、MN = 15/2厘米
2、AB = 12厘米
3、AB = 2MN