Every triangle equals 180 degrees, and we're trying to find the angle of DBA. So, we can identify DAB as a 90 degree angle to start. Then we can identify that ACB = ADB, meaning ADB is 30 degrees. With that information, we have this equation:
DBA = 180 - 90 - 30
DBA = 60
Answer:
3.Transitive Property Of Congruence
Ik this is late but the answer is A