1. Understanding Solid Figures
A Mini Lesson by Diana Dell

2. 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.

3. Examples of solid figures:
cube
sphere
triangular prism
triangular pyramid
square pyramid
cylinder
rectangular prism
cone

4. 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.

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

6. Examine some solid figures by watching this video clip.

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

8. 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.

9. 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.

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

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

12. 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.

13. 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!