∵AE为∠ADB的平分线,∴∠DAE=∠BAE,∵DC∥AB,∴∠BAE=∠DFA,∴∠DAE=∠DFA,∴AD=FD,又F为DC的中点,∴DF=CF,∴AD=DF=DC=AB=2,在Rt△ADG中,根据勾股定理得：AG=则AF=2AG=2在△ADF和△ECF中,∴△ADF≌△ECF（AAS）,∴A...