Proof: from folding, we know that AD=FD, AE=FE,

∴D and E are both on the perpendicular of AF,

∴DE vertically divides AF,

∴DE⊥AF。

⑵AD=DF，AE=CE .∠A=∠DFE，

∠ Ade =∠FDE,

AED= federal reserve.