△ABC中,AB=AC,∠A=36°,BC=6,则角平分线BD=_.

问题描述:

△ABC中,AB=AC,∠A=36°,BC=6,则角平分线BD=______.

∵△ABC中,AB=AC,∠A=36°
∴∠ABC=∠C=72°
∵BD为角平分线
∴∠ABD=∠DBC=

1
2
∠ABC=36°
∴∠C=∠CDB=72°
∴BC=BD=6.
故答案为6.