Question

Derek wrote the following paragraph proof for the Vertical Angles Theorem:

Answer 1

The phrase that would complete the proof is this:
Angle 2 is equal to Angle 4.

Vertical angles are angles formed when two lines intersect each other. The angles that are opposite each other are equal by a series of supplementary, complementary, and transitive property proofs.

Answer 2

The answer would be Angle 1 is equal to angle 3 by the subtraction property of equality.