Faces, edges and vertices of prisms and pyramids, the nets that fold into them, and how to read and draw a plan, a front elevation and a side elevation.
What you will learn
- Count the faces, edges and vertices of a prism or pyramid
- Match a net to the solid it folds into
- Read a plan of a stack of cubes
- Draw the front and side elevations of a solid
Faces, edges and vertices
A face is a flat surface, an edge is where two faces meet, and a vertex is a corner.
The plural of vertex is vertices.
- a prism on a shape with k sides: 2 ends + k rectangles = k + 2 faces
- edges: k on each end + k along the length = 3k
- vertices: k on each end = 2k
- a pyramid on a shape with k sides: k + 1 faces, 2k edges, k + 1 vertices
The point at the top of a pyramid is its apex: it is one of the vertices.
A quick check that works for all of these: faces + vertices − edges = 2. A cube has 6 faces, 8 vertices and 12 edges, and 6 + 8 − 12 = 2.
The rest of this lesson and its 7 practice questions are locked.
In this lesson
- Faces, edges and vertices
- Nets
- Plans and elevations
- Try it: An easy one first
7 practice questions, marked as you go; about 20 minutes in all.
Key terms
Face, Edge, Vertex, Net, Plan, Front elevation, Side elevation
In this unit: Area, perimeter and volume
Perimeter and area of rectangles, triangles, parallelograms, trapeziums and compound shapes, circles, arcs and sectors, and the volume and surface area of prisms, cylinders, pyramids, cones and spheres.
- Perimeter and area
- Circles
- Arcs and sectors
- Volume and surface area of prisms
- Cones, pyramids and spheres
- Solids, nets, plans and elevations