Step-by-step explanation:
AD ≅ BC, Given
∠BCD ≅ ∠ADC, Given
CD ≅ CD, Reflexive property
ΔBCD ≅ ΔADC, SAS congruence
∠BDC ≅ ∠ACD, CPCTC
ΔECD is an isosceles triangle, definition of isosceles
DE ≅ CE, properties of isosceles triangles
