Demonstration on how to determine if triangles are similar based on AA, SSS, or SAS similarity postulates.

This video shows a proof for the Pythagorean Theorem by breaking a right triangle into two similar triangles and setting up ratios of corresponding sides.

In this lesson, you will learn how the ratios of certain sides of the triangle determine the tangent value of a particular angle by using properties of similar triangles. [2:13]

This QuickTime movie provides an opportunity to learn about the characteristics of the isosceles right triangles. As you watch and listen to the teacher and student interact it helps clarify the thinking behind applying this concept.

This QuickTime movie provides an opportunity to develop the basic geometric term, similar, by using cross multiplication to see if figures are similar. As you watch and listen to the teacher and student interact it helps clarify the...

worked examples of similar triangles.

Worked examples of similar and congruent triangles.

Sal explains how the trigonometric ratios are derived from triangle similarity considerations.

Sal uses triangle similarity to plan the perfect shot in a pool game.

This lesson will provide examples that demonstrate how two triangles would be similar by SAS triangle similarity. It is 2 of 5 in the series titled "SAS Triangle Similarity."

This lesson will provide examples that demonstrate how two triangles would be similar by SAS triangle similarity. It is 5 of 5 in the series titled "SAS Triangle Similarity."

This lesson will provide examples that demonstrate how two triangles would be similar by SAS triangle similarity. It is 1 of 5 in the series titled "SAS Triangle Similarity."

This lesson defines the phrase scale factor. It is 3 of 5 in the series titled "Scale Factors."

This lesson defines the phrase scale factor. It is 1 of 5 in the series titled "Scale Factors."

In this lesson, you'll learn the definition, proportion, and notation of similar triangles. It is 3 of 5 in the series titled "Similar Triangles."

In this lesson, you'll learn the definition, proportion, and notation of similar triangles. It is 4 of 5 in the series titled "Similar Triangles."

In this lesson, you'll learn the definition, proportion, and notation of similar triangles. It is 5 of 5 in the series titled "Similar Triangles."

In this lesson, you'll learn the definition, proportion, and notation of similar triangles. It is 1 of 5 in the series titled "Similar Triangles."

This lesson explains why similar triangles can be used to make indirect measurements, and provides an example.

This lesson will provide examples that demonstrate how two triangles would be similar by SAS triangle similarity. It is 4 of 5 in the series titled "SAS Triangle Similarity."