11.4 Three Dimensional Figures

What we will learn Classify solids Describe cross sections Sketch and describe solids of revolution

Needed vocab Polyhedron: solid that is bounded by polygons Face: side of a polyhedron Edge: line segment formed by the intersection of two faces Vertex: where three or more edges meet Cross section: intersection of a plane and the solid

Ex. 1 Classifying solids Tell if a polyhedron and name if yes Prism – if both bases are congruent Pyramid – if one base and goes to a point Use base to name then add prism or pyramid Rectangular prism Hexagonal pyramid Not a polyhedron

Ex. 2 describing cross sections What is 2D shape formed by the cut? a. hexagon b. triangle c. rectangle d. circle e. circle f. trapezoid

Ex. 3 Tell what is formed Tell what figure is formed and what is radius. Because rotating about an axis, forms a round shape 7. cone, radius 3 8. cylinder, radius 6 9. sphere, radius 7