Answer:
See below.
Step-by-step explanation:
1. Given.
2. Given
3. Definition of angle bisector.
4. BD ⊥ AC
5. They are both right angles.
6. This is common on to both triangle ABD and CBD.
7. Congruent by 2 angles and the corresponding side ( ASA?)
8. CPCTC
9. Definition of an isosceles triangle.