30, 60, 90 Triangles

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Students will be able to become familiar with the ratios of the sides of 30, 60, 90 triangles.

Big Idea

Students discover the patterns involved in a 30-60-90 triangle.

Discovering Similar Triangles with the Pattern a, a√3, 2a

20 minutes
30,60,90Triangles_DiscoverSimilarTriangles_Narrative.docx page 1
30,60,90Triangles_DiscoverSimilarTriangles_Narrative.docx page 2

Proving that These Triangles are 30, 60, 90 Triangles

15 minutes
Section Narrative as pdf document page 1
Section Narrative as pdf document page 2

Applying the Pattern

10 minutes

I ask that the students turn to the back of the Rectangle Diagrams handout.  These problems and the accompanying questions help to pull together and summarize the topic of the 30-60-90 Right Triangle.