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Nets

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This sample is an excerpt from one presentation on Nets in Boardworks Middle School Math, which contains 179 interactive presentations in total.

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Information

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Here is an example of a net:

If you cut this shape out and folded it along the dotted lines, you could stick the edges together to make a 3-D shape.

Can you tell which 3-D shape this net would make?

Introducing nets

A net is a 2-D representation of a 3-D shape.

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Folding a net

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Calculating surface area

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5 cm

6 cm

3 cm6 cm

3 cm3 cm

3 cm

It can be helpful to use the net of a 3-D shape to calculate its surface area.

Here is the net of a 3 cm by 5 cm by 6 cm rectangular prism.

Write down the area of each face.

15 cm2 15 cm2

18 cm2

30 cm2 30 cm2

18 cm2

Then add the areas together to find the surface area.

Surface area = 126 cm2

Using nets to find surface area

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Mount Wilson

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