Here's the completed two-column proof with the appropriate reasons filled in:
| Statement | Reason | |------------------------------------|------------------------------------------------| | 1. ∡A + ∡B = 180 | Linear pairs are supplementary | | 2. ∡A = ∡E | Corresponding Angles Postulate | | 3. ∡E + ∡C = 180 | Substitution | | ∠E & ∠C are supplementary | Definition of supplementary angles |
This logically shows that if n || m, the consecutive interior angles (∠A and ∠C) are indeed supplementary, which is what Payton is trying to prove.