Investigate the geometric definitions of triangles, focusing upon equilateral, isosceles, right, and scalene with detailed drawings and appropriate formulas for each. This site has links to more information on triangles.

Material to supplement instruction on isosceles triangles: a lesson with related theorems and examples; an online practice quiz for students to take and check their answers; and guidelines for proving the isosceles triangle theorem.

On this site a viewer can learn about the different types of triangles, and categorized by either angles or sides. Tutorials are also included for interior and exterior angles of triangles. A teacher resource page includes a lesson plan...

This comprehensive web lesson describes how to classify triangles by their angle and side measurements. It provides real-world examples and exercises for students to practice the skill.

Here's a great geometry activity to display students' knowledge of the different types of triangles. Provides resources and adaptations to supplement this lesson. (To access this lesson plan, you must register with Crayola.com....

[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on finding the missing angle in an isosceles triangle.

Find missing angles in isosceles triangles given just one angle. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

[Free Registration/Login may be required to access all resource tools.] Apply the properties of isosceles triangles.

[Free Registration/Login may be required to access all resource tools.] This concept will teach students the properties of isosceles triangles and how to apply them to different types of problems.

[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on finding the missing angles in triangles.

The geometry tutorial investigates the definitions and properties of triangles. Topics included are isosceles, equilateral, and right triangles. In addition, the sine and cosine laws of triangles are defined.

[Free Registration/Login may be required to access all resource tools.] Students watch a video overview and attempt practice problems on classifying triangles based on length of sides.

[Free Registration/Login may be required to access all resource tools.] Students watch a video overview and attempt practice problems on classifying triangles based on the number of equal sides.

[Free Registration/Login may be required to access all resource tools.] Students watch a video overview and attempt practice problems on classifying a triangle inside a composite figure.

Brush up on your math skills relating to the types of triangles then try some practice problems to test your understanding.

[Free Registration/Login may be required to access all resource tools.] Classify triangles by side lengths and angle measures.

[Free Registration/Login may be required to access all resource tools.] Apply the special properties of 45-45-90 right triangles.

[Free Registration/Login may be required to access all resource tools.] Classify triangles by side lengths and angle measures.

[Free Registration/Login may be required to access all resource tools.] Classifying triangles by using angle measures and side lengths.

[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to classify triangles based on their angles and sides.

[Free Registration/Login may be required to access all resource tools.] Classify different types of triangles by their side lengths.

[Free Registration/Login may be required to access all resource tools.] Recognize special right triangles and their properties.

[Free Registration/Login may be required to access all resource tools.] Finding and understanding the angle measures of triangles.

[Free Registration/Login may be required to access all resource tools.] Students watch a video tutorial and attempt practice problems on how to determine the unknown side length of a triangle.