Hello from MrBillDoesMath!
Answer:
See below
Discussion:
Triangles BAD and BCD are congruent by the SAS postulate.
* Side AD = DC because BD is the perpendicular bisector of AC.
* Angle ADB and CDB are both right angles, and hence equal, because
BD is the perpendicular bisector of AC)
Corresponding parts of congruent triangles are equal so angle BAD = angle BCD, which was to be proven.
Regards,
MrB