3D Objects (Prisms, Cylinders, Cones, Spheres) at a Glance

Three‐dimensional objects are the solid shapes you see every day, like boxes, balls, coffee cups, and cans.

Here are some helpful vocabulary terms for solids:

Face: a flat side of a 3‐dimensional object.
Base: one of two parallel, congruent sides of an object.
Edge: the intersection of two faces on a solid object. This is a line.
Prism: a solid object with two congruent and parallel faces.
Pyramid: a solid object with a polygon for a base and triangles for sides.

3D shape

Say Hello to the 3-D Shapes

Name	Properties	Picture
Rectangular Prism	A prism with rectangular bases. There are six faces. All faces meet at 90 degrees. Opposite faces are parallel.
Cube	A prism with six congruent faces. All faces meet at 90-degree angles. Opposite faces are parallel. It is a form of rectangular prism.
Triangular Prism	A prism with triangular bases. Only the bases are parallel.
Octagonal Prism	A prism with octagons for bases. Opposite faces are parallel.
Triangular Pyramid, aka Tetrahedron	A pyramid with a triangular base. A tetrahedron made up of four equilateral triangles is called a regular tetrahedron.
Square Pyramid	A pyramid with a square base.
Cylinder	A solid with two parallel circular bases. If you "unwrap" the middle section and lay it flat, it is a rectangle.
Cone	A solid with a circular base and a curved side that ends in one point It has one vertex.
Sphere	A solid figure where all points are an equal distance from the center point. It's a ball.

Examples
Exercises

Example 1

What is the area of the base of the triangular prism below?

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Example 2

Which of the following statements about the given prism is not true?

a) The two bases of the prism are congruent.
b) The two bases of the prism are perpendicular.
c) The two bases of the prism are parallel.
d) The two bases of the prism are polygons.

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