If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

### Course: Class 6 (Foundation)>Unit 9

Lesson 4: Boxes and sketches

# Intro to nets of polyhedra

Admittedly, "nets of polyhedra" sounds like the title of a bad sci-fi movie about man-eating, multi-headed fish. But in reality, nets of polyhedra are just 2D objects that wrap around 3D objects, like wrapping paper around presents. Created by Sal Khan.

## Want to join the conversation?

• wow these things are from like 5 years ago its 2020 now not 2015
• The top rated questions and answers appear first and these are generally the older ones. To see the more recent ones, change the sort order.
• I still question to this day how you draw and write on a computer so well. Especially with shapes.
• At , He says that he isn't using a computer, he's hand-drawing.
• Is the net of 4D objects a bunch on 3D objects glued together?
• Yes.

A hypercube is just like a cube, but it's 4-dimensional. A regular cube has a net made up of squares, but a hypercube has a net made up of cubes. Somehow, in the 4th dimension, you can fold cubes into cubes.

Hope this helps!
• Doesn't the base of the rectangular pyramid look like a square base?
• It does, but remember that:-
A square is a rectangle with all of its sides being equal, so in a way the base of a rectangular pyramid can possibly be in the shape of a square.
• who made the name Polyhedra
• Probably the Greeks. After all, the word comes from the Greek word Poluedros, meaning "many-sided".
• what about polygon where did it's name come from
• The word polygon has come from the convergence of two words
poly - many and gon - sides
therefore polygon is a many sided figure
hope I helped!
• So when he said that there are many other ways to open polyhedra up is that true?
• yes. a cube can be opened in a cross shape or a shape like this: _|-
• Admittedly, "nets of polyhedra" sounds like the title of a bad sci-fi movie about man-eating, multi-headed fish. But in reality, nets of polyhedra are just 2D objects that wrap around 3D objects, like wrapping paper around presents.