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Session 8 Part A Part B Part C Homework
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Session 8 Materials:

Geometry Session 8: Similarity

Similarity is one of the "big ideas" in geometry. Note that two things may be similar in colloquial English, but it is a much stronger statement to say that they are mathematically similar.

In this session, you will build on your intuitive notions of what makes a "good copy" to build a more formal definition of similarity. You will then look at applications of similar triangles, including triangle trigonometry.

For information on required and/or optional materials for this session, see Note 1.

In This Session:

Part A:

Scale Drawings

Part B:

Similar Triangles

Part C:




Learning Objectives

In this session you will learn to do the following:


Explore geometric similarity as "reasoning about proportions"


Study similar triangles


Explore some basic ideas in trigonometry

video icon

Throughout the session you will be prompted to view short video segments. In addition to these excerpts, you may choose to watch the full-length video of this session.


Previously Introduced:

New in This Session:


side-side-side (SSS) congruence
triangle inequality

angle-angle-angle (AAA) similarity
side-angle-side (SAS) similarity
side-side-side (SSS) similarity

Next > Part A: Scale Drawings

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