Credit:Ruth HartnupCC-BY-2.0

Q: A: ### Quick Answer

**A cuboid has 12 edges.** A cuboid is a box-like shaped polyhedron that has six rectangular plane faces. A cuboid also has six faces and eight vertices.

Knowing these latter two facts about a cuboid, the number of edges can be calculated with Euler’s polyhedral formula. This formula states that the number of faces (F) plus the number of vertices (V) minus the number of edges (E) equals 2, or F + V - E = 2.

By substituting 6 for V and 8 for V in this equation, it becomes 6 + 8 - E = 2, or 14 - E = 2. From this equation, it is simple to see that E equals 12.

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A:

Full Answer >**A three-dimensional rectangle is called a cuboid.**A cuboid is defined as a closed box that is composed of six rectangular faces joined at right angles. The rectangles on opposite faces of the cuboid are identical to each other.Filed Under: - Q:
## What is the way to make an icosahedron?

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Full Answer >**To make an icosahedron, create a template with 20 attached triangles, then fold the sides and glue the triangles on their edges to make the figure.**An icosahedron is a geometric figure with 20 faces, 30 edges and 12 vertices.Filed Under: - Q:
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A:Draw the design of 12 pentagrams from cardstock, cut the design out, fold along all the lines, then glue or tape the edges together where they meet.

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