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.

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.

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.
 

 
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.

anonymous · Answer

http://learn.flvs.net/webdav/assessment_images/educator_geometry_v14/pool_Geom_3641_1000_Subtest_01_02/image0014e8c4bc3.jpg

anonymous · Answer

I think it's either the second or fourth one..

anonymous · Answer

hmmm....

anonymous · Answer

this one is a little more tricky

anonymous · Answer

my guess is Alternate interior angles formed by parallel lines and their transversal are congruent but u don't have that as an answer

anonymous · Answer

Isn't that D?

anonymous · Answer

ya it would be ;D