证明△ABF全等于△BCF
∵AB⊥CB
∴∠ABF+∠FBC=90°
同理可得 ∠A+∠ABF=90°
∠C+∠FBC=90°
∴∠ABF=∠C
∠A=∠FBC
∴△ABF全等于△BCF(ASA)
∴AE=BF
∴CE=BE=BF+EF=AE+EF
证明△ABF全等于△BCF
∵AB⊥CB
∴∠ABF+∠FBC=90°
同理可得 ∠A+∠ABF=90°
∠C+∠FBC=90°
∴∠ABF=∠C
∠A=∠FBC
∴△ABF全等于△BCF(ASA)
∴AE=BF
∴CE=BE=BF+EF=AE+EF