70

complete the two-column proof.

given: < 2 ≅ < 4, m< 2=110°
proof: m< 3 = 70°
m∠2 = m∠4 definition of congruent angles
m∠4 = 110º b.
∠3 and ∠4 are a linear pair definition of a linear pair (shown in diagram)
∠3 and ∠4 are supplementary linear pair postulate
m∠3 + m∠4 = 180º c.
m∠3 = 70º d.