2D shapes and 3D objects

2D shapes are flat, plane shapes. Triangles have three sides and three angles that add up to 180°. Quadrilaterals have four sides and four angles that add up to 360°.

Learn how to construct triangles using a pencil, a piece of paper, a ruler, a protractor and a compass.

3D objects have three dimensions - length, width and depth. Prisms are 3D objects with a constant cross section. Pyramids are 3D objects with a flat base and which taper to a vertex. Many three-dimensional objects can be constructed from 2D nets.