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.

In this activity, students construct isosceles and equilateral triangles. They discover that if two sides of a triangle are congruent, then the angles opposite them are congruent. They understand that an equilateral triangle is also...

This site gives a short interactive quiz which allows students to self-assess their understanding of the concept of triangles and angles.

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...

MathWorld explains what an isosceles triangle is and how it compares with equilateral, and scalene triangles. The altitude and area of these triangles are also discussed.

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.

This lesson will define scalene, isosceles, and equilateral triangles. It is 1 of 5 in the series titled "Scalene, Isosceles, and Equilateral Triangles."

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....

The definition of isosceles triangle can determine whether an equilateral triangle is a special case of an isosceles triangle. Using the Cabri Jr. application, students can get a feel for which definition makes the most sense. Along the...

This activity focuses on the various ways to construct the different types of triangles such as isosceles, equilateral, right, and right isosceles triangles. Students will begin by constructing triangles based on a minimal definition of...

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 a triangle inside a composite figure.

Explains the basic concept of equilateral triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

A complete reference guide to types of triangles and triangle perimeter and area. It provides definitions and interactive animated activities that enhance further explanation.

Students can practice classifying triangles based on side lengths through a series of self-check exercises and timed learning games.

This site provides definitions of different types of polygons and figures.

[Free Registration/Login Required] This lesson presents an introduction to triangles and the methods of identifying them. It includes opportunities for students to interactively identify triangles. It also includes: assessment questions...

[Free Registration/Login may be required to access all resource tools.] In this learning module, students are presented with a composite figure and must identify the types of triangles within it. An accompanying video demonstrates a...

The division of triangles into scalene, isosceles, and equilateral can be thought of in terms of lines of symmetry. Aligns with 4.G.A.3.

This Oswego City School District site from the Regents Exam Prep Center provides an explanation of the classifications of triangles both by sides and by angles. Pictures are also included.

A list of geometry definitions and a matching activity.

[Free Registration/Login Required] This lesson covers methods of classifying triangles, both according to the length of their sides and by the measure of their interior angle.

Given an unlimited number of a specific type of equilateral, isosceles, and right triangles create as many tetrahedra as are possible. Includes printout.