AB = AC
BM = MC
Pabc = 2·(AB + BM)
AB + BM = Pabc/2 = 16
Pabm = AB + BM + AM
Pabm -Pabc = AB + BM + AM - (AB + BM ) = AM = 24 - 16 = 8
AB = AC
BM = MC
Pabc = 2·(AB + BM)
AB + BM = Pabc/2 = 16
Pabm = AB + BM + AM
Pabm -Pabc = AB + BM + AM - (AB + BM ) = AM = 24 - 16 = 8
ответ:8см