In the figure, a||b, and both lines are intersected by transversal t. Complete the statements to prove that m∠1 = m∠5.

a||b (given)

m∠1 + m∠3 = 180° (Linear Pair Theorem) m∠5 + m∠6 = 180° (Linear Pair Theorem) m∠1 + m∠3 = ∠5 + ∠6 (_)
Transitive property of equality
Alternate interior angles theorem
Alternate exterior angles theorem
vertical angles theorem
m∠3 = m∠6 (_)
Alternate exterior angles theorem
Alternate interior angles theorem
vertical angles theorem
Transitive property of equality
m∠1 = m∠5 (Subtraction Property of Equality)