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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 10 Page 419

The angle we are looking for is between the rays that start at O and pass through the points B and D.

Angle Measure: 65^(∘)
Classification: Acute angle

Practice makes perfect

Let's first identify the angle we want. The symbol ∠ BOD refers to the angle found between the rays that start at O and pass through the points B and D.

Examining the protractor, we can see that the ray traveling through B passes through 0^(∘). Also, the ray traveling through D passes through 65^(∘). By the Protractor Postulate, the measure of ∠ BOD is the difference between 65^(∘) and 0. m ∠ BOD: 65^(∘)-0^(∘)=65^(∘) Now, we can classify the angle using its measure.

Type	Measure
Acute	0^(∘)
Right	m=90^(∘)
Obtuse	90^(∘)
Straight	m=180^(∘)

Because our angle is 65^(∘), we know that it is an acute angle.

Subchapter links

Communicate Your Answer p.413

Monitoring Progress p.414-418

Exercises p.419-422