Plz with this math 20 points provide the reasons for this proof . given: line m is parallel to line n. prove: < 1 is supplementary to < 3. here is the picture of the full problem.

1. Given
2. If parallel lines are cut by a transversal, then corresponding angles are congruent.
3. Definition of congruency.
4. if parallel lines are cut by a transversal, then corresponding angles are congruent.
5. Linear pairs are supplementary.
6. Definition of supplementary.
7. Substitution
8. Definition of supplementary.

Sorry if these are wrong. I haven't done geometry in so long, but most of these are right. You might want to check number 4 and 2.

I'm sure the answer is a