3-D SHAPES

CCS: 6.G.4. Represent three-dimensional figures using nets made up of rectangles and triangles, and use the nets to find the surface area of these figures. Apply these techniques in the context of solving real-world and mathematical problems.

Objectives: Students will be able to: Identify three dimensional figures Count faces, vertices, and edges of three-dimensional shapes Represent three-dimensional figures using nets Create nets of three-dimensional shapes

What is a 3-D Shape? This is a cube height depth length It has 3 dimensions – length, height and depth. All 3-D shapes are solids.

Labelling the Parts of a 3-D Shape A Cube Edge – a line where two faces meet Face – the flat surface of a 3-D shape A cube has: 6 faces 8 vertices 12 edges Vertex (vertices) – the point where three or more faces meet (corner)

The Shapes you need to Know SPHERE SQUARE-BASED PYRAMID CONE Click on each shape to find out more about it! CUBE CYLINDER Look at this one first! TRIANGULAR PRISM REGULAR TETRAHEDRON CUBOID

Cuboid Key Feature Six faces which are all rectangles. Faces 6 Vertices 8 Edges 12 Can you work out how many faces, vertices and edges I have? Click to check your answers… Click on me to check out other shapes…

Cube Key Feature Six faces which are all squares. Faces 6 Vertices 8 Edges 12 Remember to work out how many faces, vertices and edges I have before clicking to check your answers…

Triangular Prism What’s a prism? Click here to find out… Key Feature A prism with a triangular cross-section. Faces 5 Vertices 6 Edges 9 What’s a prism? Click here to find out…

Prisms A prism is a special kind of 3D shape . Prisms have two ends which are exactly the same shape and size. If a prism is sliced parallel to one of its ends then the new exposed ends will be exactly the same as the old ones. A prism is the same shape and size all the way through. Examples of prisms: Hexagonal Prism Triangular Prism

Regular Tetrahedron Key Feature Four faces which are all equilateral triangles. Faces 4 Vertices 4 Edges 6

Sphere Key Feature Every point on the surface of the sphere is the same distance from the centre. Faces, Vertices and Corners The normal definitions of faces, vertices and edges are not appropriate for a sphere

Cylinder Key Feature A prism with a circular cross-section. Faces, Vertices and Edges The normal definitions of faces, vertices and edges are not appropriate for a cylinder.

Cone Key Feature The point of the cone is directly above the centre of the circular base. Faces, Vertices and Edges The normal definitions of faces, vertices and edges are not appropriate for a cone.

Square-Based Pyramid Key Feature Faces 5 A shape with a square base and triangular sides that meet at a point. Vertices 5 Edges 8

NETS A net is a 2D pattern that, when put together, forms a 3D polyhedron.

Nets of 3D Shapes = A net is very helpful for identifying 3D shapes Imagine cutting a cardboard box along its edges and laying it out flat. The resulting figure is called a net. top back end front bottom = A net is very helpful for identifying 3D shapes

Let’s look at another net. This is a triangular pyramid. Notice that all sides lay out to be triangles. =

Video Time Naming a three-dimensional figure Drawing a net

Check this out! HOMEWORK: Try these games to identify shapes and their Nets 3D Shapes 1 - this is a game of matching pairs. NETS Identification Game HOMEWORK: Geometry Challenge!!! Reteaching/Practice 9.7 HO