說理如下:∵EC平分∠AED,DB平分∠ADE,
∴∠AEC=
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∵∠AED=∠ADE,
∴∠AEC=∠ADB.
在△AEC和△ADB中,∠AEC=∠ADB,AE=AD,∠A=∠A,
![](http://hiphotos.baidu.com/zhidao/pic/item/562c11dfa9ec8a133180b767f403918fa1ecc09b.jpg)
∴△AEC≌△ADB(ASA)
∴AB=AC;
(2)BE=CD,BE⊥CD
∵∠EAD=∠BAC,
∴∠EAD+∠BAD=∠BAC+∠BAD,
∴∠EAB=∠DAC,
在△AEB和△ADC中,
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∴△AEB≌△ADC(SAS),
∴∠AEB=∠ADC,BE=CD,
∵∠AEB+∠DEB+∠ADE=90°,
∴∠ADC+∠DEB+∠ADE=90°①,
∵∠ADC+∠DEB+∠ADE+∠DFE=180°②,
②-①得,∠DFE=90°,
∴BE⊥CD.
綜上可得:BE⊥CD,且BE=CD.