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.

Part A:
Scale Drawings

Part B:
Similar Triangles

Part C:
Trigonometry

Homework

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


	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 cosine side-angle-side (SAS) similarity side-side-side (SSS) similarity similar sine tangent

Next > Part A: Scale Drawings

Session 8: Index | Notes | Solutions | Video