过点E作EF⊥CD于F,过点D作DH⊥BC于H,∵AD∥BC,AB⊥BC,∴∠A=∠B=90°∵CE平分∠BCD,DE平分∠ADC,∴AE=EF,BE=EF,∴EF=AE=BE=2分之一AB,∴△ADE≌△FDE,△CEF≌△CEB,∴DF=AD=2,CF=CB=4,∴CD=6,∵AB⊥BC,DH⊥BC,AD∥BC...