Education Technology

Triangle Inequalities

Published on 06/09/2008

Activity Overview

This activity will help students visualize the properties of triangles stated in the theorems. By dragging the vertices, the students can see that the properties hold regardless of the size of the triangles and which sides are the longest or shortest.

Before the Activity

Explore relationships (including congruence and similarity) among classes of two- and three-dimensional geometric objects, make and test conjectures about them, and solve problems involving them.

During the Activity

Students will:
1. Construct triangles with given conditions,
2. Determine if properties stated in theorems can be verified by their constructions and
3. Use the Calculate option to add angles and try to alter the properties of their construction by moving the vertices

After the Activity

  • Review student answers:
  • As a class, discuss questions that appeared to be more challenging
  • Re-teach concepts as necessary