Answer:
1. ∠1 and ∠3 are vertical angles. 1. Given
2. ∠1 and ∠2 form a linear pair.
∠2 and ∠3 form a linear pair. 2. Definition of linear pair
3. ∠1 and ∠2 are supplementary.
∠2 and ∠3 are supplementary. 3.
4. m∠1 + m∠2 = 180˚
m∠2 + m∠3 = 180˚ 4.
5. m∠1 + m∠2 = m∠2 + m∠3 5.
6. m∠1 = m∠3 6.
7. ∠1 ≅ ∠3 7. Given
Step-by-step explanation:
