Vertex – A point at which two or more edges meet Edge – A line segment at which two faces intersect Face – A flat surface Vertices, Edges, Faces

Name the following figures, and tell how many vertices, edges, and faces they have

Cross Sections

Definitions Polyhedron: A solid that is made up of polygons (called faces) that enclose a single region in space. Classify whether the 3-D figure is a polyhedron or not.

Convex Polyhedron: If any two points on the surface can be connected by a segment that lies on the interior, or on, the polyhedron. Classify whether the 3-D figure is a convex polyhedron or not.

Regular Polyhedron: A convex polyhedron in which all the faces are regular polygons. Classify whether the 3-D figure is a regular convex polyhedron or not.

Cross Section: The intersection of a plane and a solid. Identify the cross section of the plane and the 3-D figure. Cross Section Pyramid Plane

Classify whether the figure is a polyhedron. If it is, what kind and why? If it is not, why?

Describe the shape formed by the intersection of the plane and the 3-D figure.

If we cut the figure with a plane, parallel to the base, what shape would be formed?

If we cut the figure with a plane, perpendicular to the base, what shape would be formed?