Question

Given: y || 2
Prove: m25+ m22 + m26 = 180°

Answer 1

1. Statement: y || z

Reason: given

2. Statement: m∠1 + m∠2 + m∠3 = m∠LAM

Reason: angle addition postulate

3. Statement: m∠1 + m∠2 + m∠3 =180

Reason: def. of a straight angle

4. Statement: ∠1 ≅∠5

Reason: alternate interior angles theorem

5. Statement: ∠3 ≅∠6

Reason: alternate interior angles theorem

6. Statement: m∠1 = m∠5

Reason: def. of ≅

7. Statement: m∠3 = m∠6

Reason: def. of ≅

8. Statement: m∠5 + m∠2 + m∠6 = 180

Reason: substitution

Explanation:

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