设三个切点分别是F,G,H,DE的切点是P.
则:
BF=BH,CG=CH,DF=DP,EG=EP
BC=BF+CG
DE=DF+EG
△ADE周长=AD+AE+DE=AF+AG=4
△ABC周长=AB+AC+BC=AF+AG+BF+CG+BC=4+2BC=8.
△ABC周长是8cm.
设三个切点分别是F,G,H,DE的切点是P.
则:
BF=BH,CG=CH,DF=DP,EG=EP
BC=BF+CG
DE=DF+EG
△ADE周长=AD+AE+DE=AF+AG=4
△ABC周长=AB+AC+BC=AF+AG+BF+CG+BC=4+2BC=8.
△ABC周长是8cm.