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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 48 Page 422

Find one time when the hands of the clock form a right angle.

See solution.

Practice makes perfect

Let's begin by looking at the case when the minute hand is vertical and the hour hand is horizontal. This way we know that the hands are perpendicular and form a right angle.

Then the minute hand points at 12, and the hour hand points at three. The angle between them is therefore 90^(∘) and it is 3 o'clock.

Subchapter links

Communicate Your Answer p.413

Monitoring Progress p.414-418

Exercises p.419-422