Understanding Solid Figures A Mini Lesson by Diana Dell

What is a solid figure? A solid figure is a three-dimensional figure. “Three- dimensional” means that the figure has measures in three directions, such as length, width, and height.

Examples of solid figures: cube sphere triangular prism triangular pyramid square pyramid cylinder rectangular prism cone http://www.harcourtschool.com/glossary/math_advantage/definitions/solid_f5.html

What are the parts of a solid figure? The face is the flat surface of a solid figure. The vertex is the point where three or more edges of a solid figure meet. The vertex is sometimes called a corner. vertex The edge is the line segment where two faces of a solid figure meet.

What are the parts of a solid figure? The base is the face of a solid figure by which the figure is named. base

Examine some solid figures by watching this video clip.

Some solid figures have a curved surface. cone cylinder curved surface

What’s the difference between a prism and a pyramid? A solid figure whose base is a polygon and whose other faces are triangles with a common vertex is a pyramid. These are pyramids.

What’s the difference between a prism and a pyramid? A solid figure whose ends are congruent, parallel polygons, and whose sides are rectangles is a prism. These are prisms.

Practice counting vertices: Remember to count the vertices that you can’t see. 8 4

Practice counting faces: Remember to count the faces that you can’t see. 4 6 1

Click on the solid figure described below. I have one base and one vertex. No, a cylinder has 2 bases. No, this pyramid has 4 vertices! Yes, a cone is correct.

Click on the solid figure described below. I have 6 square faces and 8 vertices. No, this prism does not have square faces. No, this pyramid has triangular faces. Yes, cube is correct!