成人快手

  • 2D shapes and 3D objects

    • Properties of 2D shapes

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

    • Constructing triangles

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

    • Properties of 3D objects

      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.