Question

在三角形ABC中,AB=AC,点D,E,F分别在BC,AB,AC上,且BD=CF,BE=CD,∠A=42°,则∠EDF=

Answer 1

AB=AC

∠B=∠C

BD=CF、BE+CD

△CDf≌△BDE

∠BDE=∠CFD

∠A=42°

∠C=∠B=69°

∠CDF+∠CFD=111°

∠CDF+∠BDE=111°

∠EDF=69°