Q&A #19289

Geometry attributes

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From: Jeanne (for Teacher2Teacher Service)
Date: Jan 26, 2008 at 16:58:42
Subject: Re: Geometry attributes

Hi Mrs. D.,

Actually, a base is a face -- a special face. The triangle prism has 2 bases:
the triangular faces. The lateral faces are parallelograms. Most of the time
elementary school children work with RIGHT prisms where each base meet each
lateral face at right angles. In RIGHT prisms, the lateral faces are rectangles.

Pattern blocks contain examples of different types of right prisms. The
bases include hexagons, trapezoids, equilateral triangles, 2 different

For an example of a prism whose lateral faces are not rectangles, take a
stack of index cards or a deck of playing cards and slide the cards so that 2
opposite faces form a parallelogram. (Hopefully, the sketch I've created for
you below holds its spacing.)

 *--------*      *--------*
 *--------* ===>   *--------*
 *--------*          *--------*

The deck is still a prism -- a skewed prism. If you want you can slide the
cards so that none of the lateral faces form right angles with the bases.
From a single deck of cards you can form 1 right and 2 different types of
skewed prisms.

Hope this helps!

 -Jeanne, for the T2T service

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