Answer:
AD ≅ CD.
Explanation:
Statement : consider triangles ADB and DBC.
1) AB = CD
2) ∠ABD = ∠DBC
3) DB = DB
4) ⇒ ΔADB and ΔDBC are congruent triangles.
5) AD = DC.
Reasons ;
1) given, AB = CB
2) given, DB bisects ∠ ABC
3) common side of both triangles
4) as two sides and one angle are equal in both triangles
5) congruent triangles