Question

For this item, use the following:

Given: ∠8 and ∠2 are supplementary
Prove: ∠1 and ∠3 are supplementary
Statements:

∠8 and ∠2 are supplementary (Given)
m∠28 + m∠23 = 180° (Definition of supplementary angles)
m∠28 = m∠25 (Definition of Congruence)
m∠25 + m∠23 = 180° (Substitution Property of Equality)
∠25 and ∠23 are supplementary (Definition of supplementary angles)

Answer 1

The given statement uses the definition of supplementary angles to prove that ∠1 and ∠3 are supplementary.

Step-by-step explanation:

To prove: ∠1 and ∠3 are supplementary

Given: ∠8 and ∠2 are supplementary

1. ∠8 and ∠2 are supplementary (Given)
2. m∠28 + m∠23 = 180° (Definition of supplementary angles)
3. m∠28 = m∠25 (Definition of Congruence)
4. m∠25 + m∠23 = 180° (Substitution Property of Equality)
5. ∠25 and ∠23 are supplementary (Definition of supplementary angles)