Question

如图,再△ABC中,AB=AC,P再射线BD上,且角BPC=角BAC

Answer 1

且角BPC=角BAC ,设AB与PC相交与点o

△OPB∽△AOC,OP：OA=OB：OC,OP：OB=OA：OC

△AOP相似△BOC,∠APC=∠ABC,∠BPC=∠BAC ,∠CPA +∠APD =∠ABC+∠ACB

∠APD=∠ACB,∠APC=∠APD

2、∠BAC=∠BPC=∠APD=∠APC=60

在CD上截取AP=PM,连接AM,△APM是等边三角形,∠APB=∠AMC=120

∠PAM=∠BACk=60,∠PAB=∠MAC,△APB≌△AMC,CM=PB

PA+PB=PC