What is a net of a 3D figure?

A net is a 2D shape that can be folded to form a 3D figure.

A rectangular prism has the following dimensions: length = 8 units, width = 5 units, and height = 3 units. Imagine you unfold this prism into a net. What shapes would you see in the net, and how many of each shape would there be?

The net would consist of 6 rectangles: two with dimensions 8x5, two with dimensions 8x3, and two with dimensions 5x3.

Name: Surface Area of Rectangular Prisms
Author: Insta~Lesson

7th Grade · Math · 30 min

I can calculate the surface area of rectangular prisms.

1
A net is what you get when you open up a 3D figure, like cutting a cardboard box and laying it flat.
2
To find the surface area using a net, calculate the area of each region of the net and then add them together.
3
In the example, the areas of the triangles were 48 square units each, the side panels were 140 square units each, and the base was 168 square units.

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