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Counting faces and edges of 3D shapes

Learn about shapes! Discover how to count faces and edges on 3D figures. We explore a transparent shape with five faces and another shape, a square pyramid, with eight edges and five faces. It's a colorful journey into geometry!

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  • blobby green style avatar for user Harpreet Chandi
    are vertices the same as edges
    (15 votes)
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  • aqualine seedling style avatar for user barbarapastrikou
    how can i identify faces and edges of a sphere? maybe its silly to ask but i am curious.
    (8 votes)
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  • stelly yellow style avatar for user dg635583
    i am not even doing this in class
    (5 votes)
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  • starky ultimate style avatar for user ƃuᴉpɐo˥
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠘⣷⣶⣤⣄⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠸⣿⣿⣿⣿⣷⡒⢄⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢹⣿⣿⣿⣿⣿⣆⠙⡄⠀⠐⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣤⣤⣤⣤⣤⣤⣤⣤⣤⠤⢄⡀⠀⠀⣿⣿⣿⣿⣿⣿⡆⠘⡄⠀⡆⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠙⢿⣿⣿⣿⣿⣿⣿⣿⣦⡈⠒⢄⢸⣿⣿⣿⣿⣿⣿⡀⠱⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠻⣿⣿⣿⣿⣿⣿⣿⣦⠀⠱⣿⣿⣿⣿⣿⣿⣇⠀⢃⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠘⢿⣿⣿⣿⣿⣿⣿⣷⡄⣹⣿⣿⣿⣿⣿⣿⣶⣾⣿⣶⣤⣀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣀⣀⢻⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣷⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣠⣴⣶⣿⣭⣍⡉⠙⢻⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣷⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⢀⣠⣶⣿⣿⣿⣿⣿⣿⣿⣿⣷⣦⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡇⠀⠀⠀⣀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠉⠉⠛⠻⢿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡿⠻⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡷⢂⣓⣶⣶⣶⣶⣤⣤⣄⣀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠙⠻⣿⣿⣿⣿⣿⣿⣿⣿⣿⢿⣿⣿⣿⠟⢀⣴⢿⣿⣿⣿⠟⠻⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⠿⠛⠋⠉⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠤⠤⠤⠤⠙⣻⣿⣿⣿⣿⣿⣿⣾⣿⣿⡏⣠⠟⡉⣾⣿⣿⠋⡠⠊⣿⡟⣹⣿⢿⣿⣿⣿⠿⠛⠉⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣠⣤⣶⣤⣭⣤⣼⣿⢛⣿⣿⣿⣿⣻⣿⣿⠇⠐⢀⣿⣿⡷⠋⠀⢠⣿⣺⣿⣿⢺⣿⣋⣉⣉⣩⣴⣶⣤⣤⣄⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠉⠉⠛⠻⠿⣿⣿⣿⣇⢻⣿⣿⡿⠿⣿⣯⡀⠀⢸⣿⠋⢀⣠⣶⠿⠿⢿⡿⠈⣾⣿⣿⣿⣿⡿⠿⠛⠋⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠙⠻⢧⡸⣿⣿⣿⠀⠃⠻⠟⢦⢾⢣⠶⠿⠏⠀⠰⠀⣼⡇⣸⣿⣿⠟⠉⠀⠀⢀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣠⣴⣾⣶⣽⣿⡟⠓⠒⠀⠀⡀⠀⠠⠤⠬⠉⠁⣰⣥⣾⣿⣿⣶⣶⣷⡶⠄⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠉⠉⠉⠉⠹⠟⣿⣿⡄⠀⠀⠠⡇⠀⠀⠀⠀⠀⢠⡟⠛⠛⠋⠉⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣠⠋⠹⣷⣄⠀⠐⣊⣀⠀⠀⢀⡴⠁⠣⣀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣀⣤⣀⠤⠊⢁⡸⠀⣆⠹⣿⣧⣀⠀⠀⡠⠖⡑⠁⠀⠀⠀⠑⢄⣀⣀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣰⣦⣶⣿⣿⣟⣁⣤⣾⠟⠁⢀⣿⣆⠹⡆⠻⣿⠉⢀⠜⡰⠀⠀⠈⠑⢦⡀⠈⢾⠑⡾⠲⣄⠀⣀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⠀⠀⠀⣀⣤⣶⣾⣿⣿⣿⣿⣿⣿⣿⣿⣿⡿⠖⠒⠚⠛⠛⠢⠽⢄⣘⣤⡎⠠⠿⠂⠀⠠⠴⠶⢉⡭⠃⢸⠃⠀⣿⣿⣿⠡⣀⠀⠀⠀⠀⠀⠀⠀⠀⠀
    ⠀⠀⠀⠀⠀⡤⠶⠿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣋⠁⠀⠀⠀⠀⠀⢹⡇⠀⠀⠀⠀⠒⠢⣤⠔⠁⠀⢀⡏⠀⠀⢸⣿⣿⠀⢻⡟⠑⠢⢄⡀⠀⠀⠀⠀
    ⠀⠀⠀⠀⢸⠀⠀⠀⡀⠉⠛⢿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣷⣄⣀⣀⡀⠀⢸⣷⡀⣀⣀⡠⠔⠊⠀⠀⢀⣠⡞⠀⠀⠀⢸⣿⡿⠀⠘⠀⠀⠀⠀⠈⠑⢤⠀⠀
    ⠀⠀⢀⣴⣿⡀⠀⠀⡇⠀⠀⠀⠈⣿⣿⣿⣿⣿⣿⣿⣿⣝⡛⠿⢿⣷⣦⣄⡀⠈⠉⠉⠁⠀⠀⠀⢀⣠⣴⣾⣿⡿⠁⠀⠀⠀⢸⡿⠁⠀⠀⠀⠀⠀⠀⠀⠀⡜⠀⠀
    ⠀⢀⣾⣿⣿⡇⠀⢰⣷⠀⢀⠀⠀⢹⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣶⣦⣭⣍⣉⣉⠀⢀⣀⣤⣶⣾⣿⣿⣿⢿⠿⠁⠀⠀⠀⠀⠘⠀⠀⠀⠀⠀⠀⠀⠀⠀⡰⠉⢦⠀
    ⢀⣼⣿⣿⡿⢱⠀⢸⣿⡀⢸⣧⡀⠀⢿⣿⣿⠿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⡭⠖⠁⠀⡠⠂⠀⠀⠀⠀⠀⠀⠀⠀⢠⠀⠀⠀⢠⠃⠀⠈⣀
    ⢸⣿⣿⣿⡇⠀⢧⢸⣿⣇⢸⣿⣷⡀⠈⣿⣿⣇⠈⠛⢿⣿⣿⣿⣿⣿⣿⠿⠿⠿⠿⠿⠿⠟⡻⠟⠉⠀⠀⡠⠊⠀⢠⠀⠀⠀⠀⠀⠀⠀⠀⣾⡄⠀⢠⣿⠔⠁⠀⢸
    ⠈⣿⣿⣿⣷⡀⠀⢻⣿⣿⡜⣿⣿⣷⡀⠈⢿⣿⡄⠀⠀⠈⠛⠿⣿⣿⣿⣷⣶⣶⣶⡶⠖⠉⠀⣀⣤⡶⠋⠀⣠⣶⡏⠀⠀⠀⠀⠀⠀⠀⢰⣿⣧⣶⣿⣿⠖⡠⠖⠁
    ⠀⣿⣿⣷⣌⡛⠶⣼⣿⣿⣷⣿⣿⣿⣿⡄⠈⢻⣷⠀⣄⡀⠀⠀⠀⠈⠉⠛⠛⠛⠁⣀⣤⣶⣾⠟⠋⠀⣠⣾⣿⡟⠀⠀⠀⠀⠀⠀⠀⠀⣿⣿⣿⣿⣿⠷⠊⠀⢰⠀
    ⢰⣿⣿⠀⠈⢉⡶⢿⣿⣿⣿⣿⣿⣿⣿⣿⣆⠀⠙⢇⠈⢿⣶⣦⣤⣀⣀⣠⣤⣶⣿⣿⡿⠛⠁⢀⣤⣾⣿⣿⡿⠁⠀⠀⠀⠀⠀⠀⠀⣸⣿⡿⠿⠋⠙⠒⠄⠀⠉⡄
    ⣿⣿⡏⠀⠀⠁⠀⠀⠀⠉⠉⠙⢻⣿⣿⣿⣿⣷⡀⠀⠀⠀⠻⣿⣿⣿⣿⣿⠿⠿⠛⠁⠀⣀⣴⣿⣿⣿⣿⠟⠀⠀⠀⠀⠀⠀⠀⠀⢠⠏⠀⠀⠀⠀⠀⠀⠀⠀⠀⠰
    (5 votes)
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  • marcimus pink style avatar for user Christy Elizabeth Davy
    Do we have to add up all the sides together?
    (4 votes)
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  • blobby green style avatar for user Ghale, Ewan
    So this video really made me better.
    (4 votes)
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  • blobby green style avatar for user raj3473221542
    What is the difference between faces and edges?
    (2 votes)
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    • leafers ultimate style avatar for user Nama Gosselin
      The difference between faces and edges is that faces are flat surfaces of a solid shape, while edges are line segments where two faces meet. For example, a cube has six faces, each of which is a square, and twelve edges, each of which is a line segment connecting two squares. You can see an illustration of a cube with its faces and edges labeled here. A face can also be curved, such as the surface of a sphere or a cylinder. An edge can also be curved, such as the boundary of a circle or an ellipse. I hope this helps.
      (5 votes)
  • spunky sam blue style avatar for user Shanna
    What about parallelograms and
    (3 votes)
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  • duskpin ultimate style avatar for user Minh Thu Nguyen🌺🌺
    how do you find the area of a triangle?
    (1 vote)
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  • blobby green style avatar for user Mya
    What are vertices
    (1 vote)
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Video transcript

- [Instructor] How many faces does the following shape have? Pause this video and see if you can figure that out. All right, I'm assuming you paused and I'll see if we can work through it together. And I'm gonna actually try to color the faces. So we have this face over, whoops. Let me do it in this other tool. So you have this face over here in the back. So that's one face. So that's one. Then you have this face right over here. Also in the back. The only way we can see this is because they've drawn it so that it is transparent. So that is the second face. Now you have this triangular face on top. So let me color that in. So you have this triangular face on top. So that that's going to be our third face. Third face. And then you have this triangular face on the bottom. That's gonna be our fourth face. And that's going to be our fourth face. And then the key question is, are we done? It looks like I've colored all the ones that I can see, but there's one a little bit tricky here. There's the one that we are actually seeing through, there's the face, there's, let pick a color. There's the face out front that we can see through so that we can see faces one, two, and four. So that's actually going to be our fifth face. The way they've drawn it, it's like it's made out of glass. So we can see faces one, two, and four. But that is our fifth face. And so this thing has five faces. All right, let's do another example. But instead of faces, let's gonna think about, we're gonna think about edges. So how many edges does the following shape have? Pause the video and see if you can work through this. Okay, let's work through this together now. And I'm just gonna count these edges. So the edges are where two faces meet. So this is an edge right over there. So that's one edge. There's an edge back here, we can see 'cause it's transparent. That is our second edge. We have this one over here. That is our third edge. We have this one over there. That is our fourth edge. Then we have this one over here. That is our fifth edge. Now we have this here. This is our sixth edge. Let's see. All we have left is this one, which is edge number seven. And then last but not least, this edge over here, which is edge number eight. And I actually found this very valuable to color 'em in to make sure that I wasn't missing an edge or double counting an edge. So this thing has eight, eight edges. Actually, if you're curious, just for extra practice, how many faces does this have? Well, we can count those as well. This has one face back there, another face back there. So that's two faces. And then you have a third face, which is the base, this rectangular face. So that's three faces. And then you have your two faces out front. You have this face that we're seeing through, and then we have that face that we're seeing through. So even though they're asking edges just for practice, we figured out that this thing has five faces. One for the square base, and then four triangular faces for these sides to make this square pyramid. So it has eight edges and five faces.