Khan Academy
Khan Academy: Classifying Triangles by Angles
You say you can't categorize a triangle because you don't know the length of the sides. Guess what? If you know the size of the angles you can!
Khan Academy
Khan Academy: Classifying Triangles
Learn to categorize triangles as scalene, isosceles, equilateral, acute, right, or obtuse.
Khan Academy
Khan Academy: Worked Example: Classifying Triangles
Work through sample problems categorizing triangles as scalene, isosceles, equilateral, acute, right, or obtuse.
Khan Academy
Khan Academy: Quadrilateral Properties
Learn about the properties of quadrilaterals, parallelograms, trapezoids, rhombuses, rectangles, and squares.
Khan Academy
Khan Academy: Classifying Shapes by Line and Angles Types
Sal categorizes shapes based on their sides and angles.
Khan Academy
Khan Academy: Classifying Shapes by Lines and Angles
Lindsay classifies a shape based on hints about its sides and angles.