1)
∵AB=AC AD=CE BD⊥AD CE⊥AE(HL直角三角形全等判定法则)
∴△ABD≌△CAE
∴ ∠ABD=∠CAE
又∵∠ABD+∠DAB=90°
∴∠DAB+∠CAE=90°
∴BA⊥AC
2)
同1)
∵AB=AC AD=CE ∠BDA=∠AEC=90°
∴△ABD≌△CAE
∴ ∠ABD=∠CAE
又∵∠ABD+∠DAB=90°
∴∠BAD+∠CAE=90°
∴BA⊥AC
1)
∵AB=AC AD=CE BD⊥AD CE⊥AE(HL直角三角形全等判定法则)
∴△ABD≌△CAE
∴ ∠ABD=∠CAE
又∵∠ABD+∠DAB=90°
∴∠DAB+∠CAE=90°
∴BA⊥AC
2)
同1)
∵AB=AC AD=CE ∠BDA=∠AEC=90°
∴△ABD≌△CAE
∴ ∠ABD=∠CAE
又∵∠ABD+∠DAB=90°
∴∠BAD+∠CAE=90°
∴BA⊥AC