Platonic Solids: Why only five of them?

Regular polygons are polygons with congruent sides and congruent interior angles.  In three dimensions, the equivalent of regular polygons are regular polyhedra — solids whose faces are congruent regular polygons.  The most common regular polyhedron is the cube whose faces are congruent squares.  The other regular polyhedra are shown below.

The Platonic Solids

Regular polyhedra are also known as Platonic solids — named after the Greek philosopher and mathematician Plato. The Greeks studied Platonic solids extensively, and they even associated them with the four classic elements: cube for earth, octahedron for air, icosahedron for water, and tetrahedron for fire. » Read more

Email Subscribers: Instruction on how to continue your subscription after the transfer

Unfortunately, the hosted version of Math and Multimedia will no longer have the same database for storing emails. Starting now, I will transfer all your emails to Feedburner (this is the only solution I can think of right now). This will enable you to continue receiving notifications after the transfer.

You will receive an email from Feedburner asking you to confirm your subscription. To continue your subscription, just click the confirmation link in the email (see sample email below).

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Thank you very and my apologies for the inconvenience.

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