To correctly complete the proof that consecutive interior angles are supplementary, you need a reason that justifies the equality of angles A and E.
The correct response here is:
Corresponding Angles Postulate
Here's a brief overview of how that fits into the proof:
- In statement 2, you're stating that angles A and E are equal due to their positions as corresponding angles (when two parallel lines are cut by a transversal, the corresponding angles are congruent).
So, the completed proof would look like this:
Statements Reasons
- m∡A+m∡C=180°
- Linear Pairs are supplementary
- m∡A=m∡E
- Corresponding Angles Postulate
- m∡E+m∡C=180°
- Substitution
- ∠E and ∠C are supplementary
- Definition of Supplementary Angles
Thus, the answer is Corresponding Angles Postulate.