In this lesson students apply the concepts of trigonometry to two different situations. In the first, students need to interpret a diagram with limited information to find a way to calculate the dimensions of a polygon. In the second, students are given information about a plane’s flight path, but they need to draw their own diagram as well as grapple with converting units. In each of these situations, students are making sense of problems (MP1) before they are able to use trigonometry to solve the problem.
Lesson overview
 10.1 Warmup: Notice and Wonder: Practicing Perimeter (5 minutes)

10.2 Activity: Growing Regular Polygons (20 minutes)
 Includes "Are you Ready for More?" extension problem
 10.3 Activity: Gentle Descent (10 minutes)
 Lesson Synthesis
 10.4 Cooldown: Again with Area (5 minutes)
Learning goals:
 Use trigonometry to solve problems (using words and other representations).
Learning goals (student facing):
 Let’s solve problems about right triangles.
Learning targets (student facing):
 I can use trigonometry to solve problems.
Required materials:
 Geometry toolkits (HS)
 Scientific calculators
Required preparation:
 Be prepared to display applets for all to see throughout the lesson.
Standards:
 This lesson builds towards the standards: CCSS.HSGGMD.A.1MS.GGMD.1CCSS.HSGSRT.C.8MS.GSRT.8MO.G.GMD.A.1MO.G.SRT.C.7
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