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Given: Lines y and z are parallel, and ABC forms a triangle. Prove: m∠5 + m∠2 + m∠6 = 180° Statements Reasons 1. ABC is a triangle 1. given 2. y ∥ z 2. given 3. ∠1 ≅ ∠5; ∠3 ≅ ∠6 3. ? 4. m∠1 = m∠5; m∠3 = m∠6 4. def. ≅ 5. m∠1 + m∠2 + m∠3 = m∠LAM 5. ∠ addition postulate 6. m∠1 + m∠2 + m∠3 = 180° 6. def. straight angle 7. m∠5 + m∠2 + m∠6 = 180° 7. substitution Which could be the missing reason in Step 3?

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2 votes

Answer:

This took me so long lol...

Explanation:

Given: Lines y and z are parallel, and ABC forms a triangle. Prove: m∠5 + m∠2 + m-example-1
User Matt Fellows
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3 votes
alternate interior angles are congruent

User Doctore
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8.7k points