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Big Ideas Math Integrated I, 2016

BI

Big Ideas Math Integrated I, 2016 View details

6. Describing Pairs of Angles

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Exercise 42 Page 429

What can the measure of an acute angle be? What does it mean if two angles are supplementary?

See solution.

Practice makes perfect

If ∠ A is an acute angle, we can give its measure an upper and lower bound. 0^(∘) < m∠ A < 90^(∘) If ∠ S is supplementary to ∠ A, it means that the sum of their measures is 180^(∘). m∠ A+m∠ S=180^(∘) Since m∠ A is less than 90^(∘), that means m∠ S must be greater than 90^(∘) for the sum of their measures to be 180^(∘). Therefore, ∠ S must be obtuse.

Subchapter links

Communicate Your Answer p.423

Monitoring Progress p.425-427

Exercises p.428-430