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7th Grade Math / Lesson 4: 3-Dimensional Objects

3-DIMENSIONAL OBJECTS
What will we be learning in this lesson?


  • In this lesson, you will look at aspects of 3-dimensional objects. You will also attempt to draw sketches of these objects.


3-DIMENSIONAL OBJECTS


  • Shapes on paper are 2-dimensional. They have a length and a width.

  • Objects in real life are 3-dimensional. They have a length, a width, and also a depth.


3-DIMENSIONAL OBJECTS


  • The faces of these objects are 2-dimensional shapes. Like the object below. The faces of the object are rectangles.

  • Where two faces of an object meet is called an edge.


3-DIMENSIONAL OBJECTS


  • The point where edges come together is called a vertex.

  • Objects can be seen at different angles. Compare this object to the one above. It is the same box, but you can see the left side of the box, where the one above, you can see the right side of the box.


3-DIMENSIONAL OBJECTS


  • Drawing a 3-dimensional object can be difficult if you do not have the shading capabilities like I did in this program. This shape has rectangles as all of its faces.

  • Objects that have squares on all sides is called a cube.
  • Objects that have triangles on all sides is called a tetrahedron.


  • Can you sketch a 3-dimensional object from different angles.