Question

Amanda is writing a proof for the theorem stated below.

Theorem: The sum of interior angles of a triangle is 180°.

She first drew the figure shown below.

Answer 1

Which theorem will she most likely use in the proof?

Supplements of congruent angles are congruent.

If two angles of a triangle are congruent, the sides opposite these are congruent.

All straight angles are congruent.

Corresponding angles formed by parallel lines and their transversal are congruent.

Answer 2

Well, look at the angles as she has labeled them. Which angles does she put the same number on? What theorem would you use to show that these angles are congruent?

Answer 3

c?