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Big Ideas Math Integrated I, 2016

BI

Big Ideas Math Integrated I, 2016 View details

5. Measuring and Constructing Angles

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Exercise 13 Page 419

Should you use the upper or lower measure on the protractor?

See solution.

Practice makes perfect

The symbol ∠ AOC refers to the angle that's in between the rays that starts at O and passes through the points B and C.

The ray through C points to both 30^(∘) and 150^(∘). The lesser of these, 30^(∘), is used when you are coming in from the left on the protractor. The larger measure is used when coming in from the right. Measuring ∠ BOC, we are coming in from the right.

The error is therefore using the incorrect measure on the protractor and the correct measure is 150^(∘).

Subchapter links

Communicate Your Answer p.413

Monitoring Progress p.414-418

Exercises p.419-422