如图,AC∥BD,AE,BE分别平分∠CAB和∠DBA,点E在CD上. 求证:AB=AC+BD.

问题描述:

如图,AC∥BD,AE,BE分别平分∠CAB和∠DBA,点E在CD上.
求证:AB=AC+BD.

证明:如图,在AB上截取AF=AC,连接EF,在△CAE和△FAE中,AC=AF∠CAE=∠FAEAE=AE,∴△CAE≌△FAE(SAS),则∠CEA=∠FEA,又∠CEA+∠BED=∠FEA+∠FEB=90°,∴∠FEB=∠DEB,∵BE平分∠DBA,∴∠DBE=∠FBE,在△...