In this activity, students investigate properties of triangles by randomly generating possible side lengths for triangles. They learn to determine if three line segments can form a triangle. They also learn to classify triangles as...

Practice identifying triangles by their side-lengths as equilateral, isosceles, or scalene. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

Three circles are mutually tangent. Students are asked to find the total area of the circles plus the area inside where they meet. Students will need to know how to calculate the area of a circle, a sector of a circle, and an equilateral...

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.

Students learn abouT the Law of Reflection by constructing an equilateral triangle using graph paper, pencil, protractor, and a ruler and a "laser triangle" using a laser pointer and front-silvered mirrors.

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

With this math site you will find the distinguishing characteristics of a rectangular hyperbola and other frequently used terms when referring to this special hyperbola. This site also gives formulas, pictures, and links.

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

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

[Free Registration/Login may be required to access all resource tools.] Identify special triangles and use the characteristics of 30-60-90 triangles in problem solving.

[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.

[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.

Students are assessed on different types of triangles. Definitions of the triangles are included.

A labeled illustration of six different types of triangles.

In this lesson, students learn to inscribe regular polygons inside a circle.

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.

Learn about the types of triangles by taking a look at an example and a video lesson.

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

Learn about the properties of 2-D shapes: circles, triangles, polygons, and quadrilaterals. Includes information, video, and examples about each, with games and quizzes for reinforcement.

[Free Registration/Login may be required to access all resource tools.] This study guide reviews terminology for triangles, triangle properties, different types of triangles, and interior and exterior angle theorems.

A reference guide to isosceles triangles. It provides a definition and interactive animated activity that enhances further explanation. Includes links to related topics.

A complete reference guide to the circumcircle of a triangle. It provides definitions, examples, and an interactive activity that enhances further explanation. Includes links to related topics.

Learn about the Euler line with this handy reference guide. Provides a detailed definition and an interactive activity that enhances further explanation. Includes links to related topics.

A complete reference guide to irregular polygons. It provides definitions and an interactive activity that enhances further explanation. Includes links to related topics.