Identify the missing parts in the proof Given: ABC is a right angle
DB bisects ABC
Prove: mCBD=45 degrees

A:
division,
definition of bisects,
definition of right angle,
given
B:
measure of angle ABC=90
Measure of angle ABC=180
Measure of angle ABD=90
Measure of angle CBD=180
C:
Addition
Angle addition postulate
Definition of right angle
Substitution property
D:
Angle ABC=90
Angle ABD=90
2 times the measure of angle ABC=90
2 times the measure of angle CBD=90