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How to Make a Triangular Prism out of Cardboard

A polyhedron is a three-dimensional geometric solid with flat faces. "Poly" is Greek for "many," and "hedron" means "faces." Every polyhedron has a certain number of sides, vertices and faces. Sides are where two faces meet; vertices are the points at which more than two faces meet, and faces are the flat polygon shapes in the polyhedron. A triangular prism is a polyhedron called a "pentahedron," meaning "five faces." The two ends of the triangular prism are triangles, and the three sides are rectangles. To make a triangular prism or any other polyhedron, a net is required. A net is a two-dimension design on paper that can be folded into a three-dimensional shape.

Instructions

- 1
  Draw an equilateral triangle on a thick piece of paper.
- 2
  Draw a rectangle attached to the bottom of the triangle; the top line of the rectangle is the bottom line of the triangle.
- 3
  Draw an exact mirror image of the first equilateral triangle on the bottom of the rectangle so that the bottom line of the rectangle is the top line of the upside-down triangle.
- 4
  Draw two rectangles identical to and attached to the first. One will be directly to the left of the first and the other will be directly to the right of it.
- 5
  Cut out around the perimeter. Do not cut any of the interior lines.
- 6
  Fold the triangles up so they are perpendicular to the rectangles.
- 7
  Fold the left and right rectangles up so the edges meet the edges of the triangle. Tape into place.

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