+149 Provide statements and reasons in the proof of the triangle angle bisector theorem. Given: line BD bisects angle ABC. Prove: AD/DC=AB/BC
Draw a line through point A and parallel to line BD. Let point E be the intersection of this line and the line that contains line BC.
1. line BD bisects angle ABC. 1. Given
2. AD/DC=EB/BC 2. Triangle Proportionality Theorem
3. 4. 4. Definition of bisect
5. 6. 7. 8. line EB=line AB 8.
9. 9. Segment Congruence Postulate
10. 10. Substitution Property of Equality
