Answer:
This proof involves the definitions of congruence and supplementary angles, as well as some of the properties of equality.
∠1 and ∠2 are supplementary // given
∠3 and ∠4 are supplementary // given
∠1 ≅ ∠3 // given
m∠1 + m∠2 = 180° // definition of supplementary angles
m∠3 + m∠4 = 180° // definition of supplementary angles
m∠1 + m∠2 = m∠3 + m∠4 // transitive property of equality
m∠1 = m∠3 // definition of congruent angles
m∠1 + m∠2 = m∠1 + m∠4 // substitution property of equality (replaced m∠3 with m∠1)
m∠2 = m∠4 // subtraction property of equality (subtracted m∠1 from both sides)
∠2 ≅ ∠4 // definition of congruent angles
hope this helps
Step-by-step explanation:
