Surface Area of Rectangular Prisms Notes

Lesson 9-2: Surface Area of Rectangular Prisms

Learning Objective

• Represent a rectangular prism with its net to find the surface area in mathematical and real-world contexts.

Vocabulary

• Net: A two-dimensional representation of a three-dimensional figure.

• Surface Area: Not explicitly defined here, but implied as the sum of the areas of all faces of a 3D figure.

Explore Cube Nets

• Online activity involving models to explore nets of prisms.

Make a Net to Represent a Rectangular Prism

• A net is constructed by deconstructing a three-dimensional figure into its two-dimensional faces.

• A rectangular prism has six rectangular faces.

• Opposite faces of a rectangular prism are congruent:

  • Top and bottom faces are congruent.

  • Front and back faces are congruent.

  • The two side faces are congruent.

Example Dimensions

• Given a rectangular prism, its net shows how the faces unfold.

• Example dimensions:

  • Length = 4 in.

  • Width = 2 in.

  • Height = 3 in.

• Net representation:

  • The net includes the following faces: back, side, bottom, side, top, front.

  • Dimensions are labeled on the net to correspond with the 3D prism. For example:

    • back: 3 in. x 4 in.

    • side: 3 in. x 2 in.

    • bottom: 4 in. x 2 in.

    • front: 3 in. x 4 in.

    • top: 4 in. x 2 in.

    • side: 3 in. x 2 in.

• The length, width, and height of the prism correspond directly to the dimensions on the net.