Interactive Triangles

Read about Triangles, and then play with them here.
They rotate, too! So you can become familiar with them from all angles.

images/triangle.js?mode=choose

Try These Challenges!

In "Any" mode: drag the corners of the triangle to see if you can make:

  • An Equilateral Triangle (all three sides the same length, and all angles 60°)
  • A Right Triangle (one angle exactly 90°)
  • An Obtuse Triangle (one angle greater than 90°)