Math Humor

LT 10.1: Classify 3D figures according ot their properties and use Euler’s formula to find number of vertices, edges and faces.

A cube is a prism with six square faces A cube is a prism with six square faces. Other prisms and pyramids are named for the shape of their bases.

Three-dimensional figures, or solids, can be made up of flat or curved surfaces. Each flat surface is called a face. An edge is the segment that is the intersection of two faces. A vertex is the point that is the intersection of three or more faces.

A polyhedron is formed by four or more polygons that intersect only at their edges. Prisms and pyramids are polyhedrons, but cylinders and cones are not.

Example Classify the figure with the following: 4 vertices, 6 edges, 4 faces Triangular Pyramid 15 edges, 7 faces, 10 vertices Pentagonal Prism 9 edges, 6 vertices, 5 faces Triangular Prism

Classify each figure Triangular Prism             Pentagonal Pyramid                       Triangular Prism

EULERS FORMULA For any polyhedron with V vertices, E Edges, and F faces: V – E + F = 2

Bonus Math Humor Who was the Tin Man’s favorite mathematician? Euler!

Example Find the number of vertices, edges, and faces of each polyhedron. Use your results to verify Euler’s Formula. V – E + F = 2                                V – E + F = 2 4 – 6 + 4 = 2                               10 – 15 + 7 = 2