Question

初二数学，谢谢！！

Answer 1

∵BD平分∠ABC，那么∠CBD=∠ABD=1/2∠ABC
∴∠C+∠CBD=180°-∠BDC=180°-95°=85°
即∠C+1/2∠ABC=85°
∵∠ABC+∠C=180°-∠A=180°-60°=120°
∴∠C=120°-∠ABC，∠C=85°-1/2∠ABC
那么120°-∠ABC=85°-1/2∠ABC
∠ABC=70°
∴∠CBD=∠ABD=1/2∠ABC=35°
∵DE∥BC
∴∠EDB=∠CBD=35°
∵∠EBD=∠ABD=35°
∴∠BED=180°-∠EDB-∠EBD=180°-35°-35°=110°

Answer 2

1. ∠DBC+∠C=180°-∠BDC=85°

2. 2∠DBC+∠C=180°-∠A=120°

　　由等式2-等式1得：∠BDC=35°，则∠EBD=35°，∠ABC=70°

由DE∥BC，得∠AED=∠ABC=70°，则∠BED=180°-∠AED=110°

∠BDE=180°-∠BED-∠EBD=35°

　　

Answer 3

35度，三角形一个外角等于与之不相邻的两个内角和