Question

如图15,AB=AC,CD垂直于AB于D,BE垂直于AC于E,BE、CD相交于F,连接AF,求证∠BAF=∠CAF.

Answer 1

证明∵ab=ac

cd⊥ab于d,be⊥ac于e

∠adc=∠aeb=90

∠dac=∠ead

∴△adc全等△aeb

∴ad=ae

∠adc=∠aeb=90

af=af

∴△adf全等△aef

∠baf=∠caf