Question

The figure below shows line PQ parallel to line RS. The parallel lines are cut by the transversal XY.

Which fact is used to prove that angles PMN and MNS are congruent?
The measure of the sum of corresponding angles is greater than 180°.

The sum of vertically opposite angles is supplementary.

The measure of the sum of alternate angles is greater than 180°.

The alternate interior angles are congruent.

Answer 1

@NaCl Can you help?

Answer 2

@FilthyMcNasty HEY!

Answer 3

:D

Answer 4

Recall this theorem:

If two parallel lines are cut by a transversal, then alternate interior angles are congruent. @LilyMysterix

Answer 5

The alternate interior angles are congruent.

Answer 6

Oh. That's right. Thanks @Directrix.
Thanks, @NaCl.(: