In the figure, a||b , and both lines are intersected by transversal t. Complete the statements to prove that ∠2 and ∠8 are supplementary angles.

a||b (given)

m∠2 = m∠7 ( )

m∠7 + m∠8 = 180° ( )

m∠2 + m∠8 = 180° (Substitution Property)

∠2 and ∠8 are supplementary (definition of supplementary angles)