Ch 12 and 13 Definitions

1. polyhedron

• A solid with all flat surfaces that enclose a single region of space

2. face

• Each flat surface

• A cube has 6 faces

3. edge

• Line segments where the faces intersect

4. vertex

• The point where three planes intersect

5. prism• Polyhedron with two parallel congruent faces.• Named by their bases!• What shape are the sides?

6. Regular prism

• A prism with bases that are regular polygons

7. pyramid• A polyhedron with all faces (except for one)

intersecting at one vertex

8. Regular polyhedron• ALL of its faces are regular, congruent

polygons and all edges are congruent

9. Platonic solids

• Exactly 5 types of regular polyhedronTetrahedron (4 equilateral triangles)Hexahedron (6 squares)Octahedron (8 equilateral triangles)Dodecahedron (12 regular pentagons)Icosahedron (20 equilateral triangles)

10. Cylinder

• Solid (not polyhedron) with circular bases in a pair of parallel planes

11. Cone

• (not a polyhedron)• Has a circular base and a vertex

12. Sphere

• A set of points in space that are a given distance from a given point.

• What are the 2 parallel congruent faces of a prism called?

• The faces of a prism that are not the bases are all __________________________________

Orthogonal drawings show two-dimensional views of the top, left, front, back, and right sides.

top left front right back?!

What is the 3-D shape?!