Question

The figure below shows a quadrilateral ABCD with diagonal BD bisecting angle ADC.

Which equation is true?

Angle ABD = angle BCD

Angle DCB = angle ADB

Angle ABD = angle CBD

Angle ABD = angle CDB

Answer 1

I say C

Answer 2

well, they have a tickmark.. so AB = CB and they also have an equal angle plus they also share DB

so yes, both triangles are congruent by SAS and thus ABD = CBD

Answer 3

thanks!