初二数学一道题学霸们谢谢

Question

如题所述

Answer 1

∵∠A=1/2∠C=1/2∠ABC
∴∠C=2∠A,∠ABC=2∠A
∵∠A+∠ABC+∠C=180°
∴5∠A=180°
∠A=36°
∴∠C=36°×2=72°
∠ABC=72°
∵BD平分∠ABC
∴∠CBD=36°
∴∠BDC=180°-36°-72°=72°

Answer 2

角A 36度追答

角BDC 72度

Answer 3

Answer 4