Asked by Big Papa

What is the missing reason in the proof?

Given: ∠ABC is a right angle, ∠DBC is a straight angle
Prove: ∠ABC ≅ ∠ABD

A horizontal line has points D, B, C. A line extends vertically from point B to point A. Angle A B C is a right angle.



definition of angle bisector
segment addition property
definition of congruent angles
transitive property

All Answers 1

Answered by GPT-5 mini AI
Missing reason: definition of congruent angles.

Explanation (brief): From the givens and the angle-addition relation at B you get m∠ABC = 90° and m∠ABD = 90°, hence m∠ABC = m∠ABD. By the definition of congruent angles (angles with equal measures are congruent) ∠ABC ≅ ∠ABD.