等腰梯形ABCD中,AD‖DC,∠C=60°,AD=CD,E,F分别为AD,CD上,DE=CF,AF,BE交于P.求∠BPF
问题描述:
等腰梯形ABCD中,AD‖DC,∠C=60°,AD=CD,E,F分别为AD,CD上,DE=CF,AF,BE交于P.求∠BPF
答
∵ABCD是等腰梯形,∠C=60°
∴∠BAE=∠D=120°
∵DE =CF ,AD =CD
∴AE =DF
∴△ABE≌△DAF
∴∠ABE =∠FAD
∵∠BPF =∠ABP+∠BAP
∴∠BPF =∠BAP+∠FAD=∠BAD=120°