∠AEF = 180°-∠CEF-∠CED = 90°-∠CED = ∠DCE ,
因为,∠EAF = 90°= ∠CDE ,∠AEF = ∠DCE ,
所以,△AEF ∽ △DCE ,
可得:EF∶CE = AF∶DE = AF∶AE ;
因为,∠EAF = 90°= ∠CEF ,EF∶CE = AF∶AE ,
所以,△AFE ∽ △EFC .
∠AEF = 180°-∠CEF-∠CED = 90°-∠CED = ∠DCE ,
因为,∠EAF = 90°= ∠CDE ,∠AEF = ∠DCE ,
所以,△AEF ∽ △DCE ,
可得:EF∶CE = AF∶DE = AF∶AE ;
因为,∠EAF = 90°= ∠CEF ,EF∶CE = AF∶AE ,
所以,△AFE ∽ △EFC .