Geometry: An Interactive Journey to Mastery

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Lesson 27

Topics

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x Fagnano’s problem.

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point B via a location along a given straight line is the path

that produces congruent angles, as shown in )LJXUH.

Summary

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famous problem in geometry—Fagnano’s problem—as well as explore a number of additional applications.

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Adit stands at point A at the end of a long corridor with three perpendicular walls, as shown in )LJXUH.

He wishes to throw a ball in some direction so that it bounces off all three walls and returns directly to him. In

which direction should he throw the ball? Draw the direction on this page.

A

B

x x

Figure 27.1

A

Figure 27.2