1) Given
2) m∠1 + m∠2 = 90°
3) BD bisects ∠ADC
4) definition of angle bisector
5) definition of congruency
6) m∠1 + m∠3 = 90°
7) ∠1 is complementary to ∠3 (7) definition of complementary
If there is a drop down box, and my answer is not an option, type in the options in the comment box and I will let you know which theorems (or definitions) are the same as my answer.
