2-D or 3-D?— Let's Practice!

2-D or 3-D?— Let's Practice! exercise

• Which are flat and which are solid?

  Hints

  A flat shape does not have any faces. These are 2-D.

  A 3-D shape has faces.

  Solution

  The first group of shapes are all 2-D because they are flat.

  The second group of shapes are 3-D because they are solid.

• Are these shapes 2-D or 3-D?

  Hints

  Remember, 3-D shapes are solid.

  2-D shapes are flat.

  Solution

  The sphere and the prism are 3-D because these shapes are solid.

  The circle and the triangle are 2-D because the shapes are flat.

• What type of shape is it?

  Hints

  3-D shapes look solid and real.

  2-D shapes look flat.

  Solution

  • The cone is 3-D.
  • The cuboid is 3-D.
  • The rectangle is 2-D.

• Are the shapes 2-D or 3-D?

  Hints

  3-D shapes look solid. They have faces, edges and vertices.

  2-D shapes look flat. They have sides.

  Solution

  The square and circle are 2-D shapes.

  The cylinder and pyramid are 3-D shapes.

• Are they 2-D or 3-D?

  Hints

  • 2-D shapes look flat or like drawings.
  • 3-D shapes look real.

  This is an example of a 3-D shape.

  Solution

  The square and the triangle are 2-D shapes.

  The cylinder and the cube are 3-D shapes.

• How many of each shape type are there?

  Hints

  Here is an example of a 3-D shape.

  Here is an example of a 2-D shape.

  Solution

  There are four 3-D shapes: cylinder, cube, sphere and cuboid.

  There are three 2-D shapes: pentagon, kite and heart.