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Big Ideas Math Integrated I, 2016

BI

Big Ideas Math Integrated I, 2016 View details

3. Proofs with Parallel Lines

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Exercise 19 Page 514

Do we know how x and y compare?

Conclusion: a ∥ b if x=y.
Explanation: See solution.

Practice makes perfect

Just because the vertical angles are congruent, it does not necessarily mean that a and b are parallel. We need to know how x and y compare. If we had

x=y, the conclusion would be correct. But we do not know that. It's just looks like the lines are parallel so the conclusion has to include that x equals y.

Subchapter links

Communicate Your Answer p.509

Monitoring Progress p.510-513

Exercises p.514-516