Triangle Classification by Sides

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About This Diagram

This diagram shows the three classifications of triangles based on the relationships among their side lengths.

Triangle Types by Sides

Type	Definition	Properties
Scalene	All three sides different lengths	No equal angles
Isosceles	Two sides equal (congruent)	Base angles are equal
Equilateral	All three sides equal	All angles are 60°

Visual Markers

• Tick marks on sides indicate congruent (equal) sides
• Arc marks at angles indicate congruent angles
• Side lengths are labeled in centimeters

Key Facts

• An equilateral triangle is a special type of isosceles triangle
• Every triangle falls into exactly one of these categories

Interaction

Click on any triangle panel to highlight that type and dim the others.

Learning Objectives

• Remember the three classifications by sides
• Understand the relationship between equal sides and equal angles

Bloom's Taxonomy Level

Remembering and Understanding - Terminology introduction.

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