Quadrilaterals

Quadrilaterals only have one side more than triangles, but this opens up an entire new world with a huge variety of quadrilateral types. Learn about it here.

Not all things with four sides and 90 degree angles are squares or rectangles! Sometimes the angles in these 4-sided shapes are less than (or greater than) 90 degrees, causing them to have a slightly odd shape. These are called quadrilaterals and come in a few different varieties. In this tutorial, you'll learn about them.