Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
5. Measuring and Constructing Angles
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Exercise 15 Page 420

Start by drawing an arc through the original angle.

Practice makes perfect

We want to use a compass and straightedge to copy the given angle. To copy the angle, we start by drawing an arc across the original angle creating points B and C. Then, using the same settings on our compass, we will draw the same arc across a horizontal arrow like below, creating E.

Next, we change the settings on our compass to measure the distance between B and C. Keeping this measurement, we mark this distance on the arc of our copy starting at E and calling the intersection F.

Finally, we have two points, D and F that lie on the second arm of the copied angle. Therefore, we can draw a ray through DF to complete copying the given angle.