3. Planes
A PLANE is a flat surface with no
thickness.
Our world has three dimensions,
but there are only two
dimensions on a plane:
• Length and width make a plane
• x and y also make a plane
Two converged
planes!
4. Prisms
A PRISM is a solid
object with:
• identical parallel
ends
• flat faces
• and the same cross
section all along its
length
A skyscraper is a
fantastic example!
5. Cubes
A CUBE is a solid
formed by six identical
square faces joined
together along their
edges.
• Each of its 8 corners is
called a vertex.
• The cube can also be
called a regular
hexahedron. Just like the
Rubik’s cube!
6. Pyramids
A PYRAMID is
a polyhedron that has
a base (which can be
any polygon) and
three or more
triangular faces that
meet at a point called
the apex.
• These triangular
sides are also called
the lateral faces to
distinguish them from
the base. The pyramids in Egypt are a good example!
7. Cylinders
A CYLINDER is a closed
solid that has two
parallel circular bases
connected by a curved
surface.
• It has a flat base and
a flat top
• It’s not a polyhedron
as it has a curved
surface
Think of a paper bin!
8. Cones
A CONE is a solid
that has a circular
base and a a single
vertex. If the vertex
is over the center
of the base, it is
called a right cone.
If it is not, it is
called an oblique
cone.
A traffic cone is
an ideal example!
9. Spheres
• A SPHERE is a solid
geometric figure
generated by the
revolution of a semicircle
about its diameter.
• A round body whose
surface is at all points
equidistant from the
centre. What better
example than a
football!
10. Euler´s Theorem
For any polyhedron that
doesn't intersect itself, the…
• Number of Faces
• plus the Number of
Vertices (corner points)
• minus the Number of Edges
• always equals 2
V - E + F = 2
V = 8, E = 12 and F = 6
V - E + F = 8 - 12 + 6 = 14 - 12 = 2
The formula has the name of the famous Swiss
mathematician Leonhard Euler (1707 - 1783)
