证明:(1)如图,∵∠ADE=∠C,∠A=∠A,∴△ADE∽△ACD;(2)如图,∵AE=2,EC=3,∴AC=AE+EC=5.∵由(1)知,△ADE∽△ACD.∴ AE AD = AD AC ,即 2 AD = AD 5 ,解得,AD= 10 .∵AB= 10 ,∴AB=AD.∴∠B=∠ADB,由△ADE∽△ACD知,∠AED=∠ADC,∴∠CED=∠ADB.∴∠CED=∠B.