Can a rectangle be a sqaure?

a square can be a rectangle but a rectangle cannot be a square

What is a shape called if it has 100 sides?

For short, it can be a 100-gon, but it is called zocchihedron.

Can something have a different amount of sides and corners? Like 4 sides and 5 corners?

accutually, a 'v' has two sides and one corner. Open shapes will have a different number of sides and corners, closed shapes will not.

What are 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 sided shapes called. Also Thank you

3 sided shapes are called triangles, 4 sided shapes are called quadrilaterals, 5 sided shapes are called pentagons, 6 sided shapes are called hexagons, 7 sided shapes are called heptagons, 8 sided shapes are called octagons, 9 sided shapes are called nonagons, 10 sided shapes are called decagons, 11 sided shapes are called hendecagon, 12 sided shapes are called dodecagon.

I've always thought corners meant where two lines meet at a 90 degree angle, but is it really just where two lines meet together? Mainly I'm asking about at 2:57 and at 2:06.

In shapes, a corner is any place at which two lines meet. In real life, you most often encounter corners that are parts of rooms, or tables, and those *should* be 90 degrees. Hope this helps!

Whats the difference between a circle and a oval?

An oval is slightly rounded or elongated, might be an ellipse, might be a circle too if it is the same shape as a circle. A circle is completely round, all the edges are the same distance away from the center. So an oval can be longer along one side than another.

Could there be a shape that has one side and one corner?

There could not be a shape with one side and one corner for two reasons. 1. The first criteria for a shape is closed. It would not be possible to close a figure with one side. 2. A figure with one side cannot form a corner. This is because a corner is formed by two sides. I hope this helps! Bill

Is there any difference between an oval and an ellipse?

Yes, there is. An ellipse is a precisely-defined mathematical figure, which has two axes of symmetry. Its shape is defined by two numbers, called the semi-major and semi-minor axes (the equivalents of the radius of a circle). The term "oval", by contrast, does not have a precise meaning, and is used for any shape which resembled an egg, with either one or two axes of symmetry.

"A trapezoid is a 4-sided flat shape with straight sides that has a pair of opposite sides parallel". Does that mean that squares and rectangles are trapezoids ?

A trapezoid cannot be a square because a square have 2 pairs of parallel sides while a trapezoid only has one pair. In this case, a rectangle cannot be a trapezoid either.

Are there any other differences between an oval and a circle (or is the length the only difference)?

An oval is a circle that is elongated in some direction. A circle could be elongated by no value at all so this holds. All circles are ovals Not all Ovals are circles

Main content

2nd grade

Course: 2nd grade > Unit 8

Lesson 1: Shapes

Cousin Fal's shape collection

Name: Cousin Fal's shape collection
Uploaded: 2014-03-22T01:37:56Z
Description: Sal classifies shapes based on their number of sides, number of corners, and side-lengths.

Google Classroom

Sal classifies shapes based on their number of sides, number of corners, and side-lengths. Created by Sal Khan.

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Zoeslight~learning
Posted 6 years ago. Direct link to Zoeslight~learning's post “What are 3, 4, 5, 6, 7, 8...”
What are 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 sided shapes called. Also Thank you
Comment on Zoeslight~learning's post “What are 3, 4, 5, 6, 7, 8...”
(6 votes)
- Merger Mystery
  Posted 6 years ago. Direct link to Merger Mystery's post “3 sided shapes are called...”
  3 sided shapes are called triangles,
  4 sided shapes are called quadrilaterals,
  5 sided shapes are called pentagons,
  6 sided shapes are called hexagons,
  7 sided shapes are called heptagons,
  8 sided shapes are called octagons,
  9 sided shapes are called nonagons,
  10 sided shapes are called decagons,
  11 sided shapes are called hendecagon,
  12 sided shapes are called dodecagon.
  Comment on Merger Mystery's post “3 sided shapes are called...”
  (36 votes)
jordansha
Posted 4 years ago. Direct link to jordansha's post “Can a rectangle be a sqau...”
Can a rectangle be a sqaure?
Comment on jordansha's post “Can a rectangle be a sqau...”
(22 votes)
- aquila.concepcion
  Posted 2 years ago. Direct link to aquila.concepcion's post “a square can be a rectang...”
  a square can be a rectangle but a rectangle cannot be a square
  Comment on aquila.concepcion's post “a square can be a rectang...”
  (19 votes)
Aditri Mallick
Posted 3 years ago. Direct link to Aditri Mallick's post “What is a shape called if...”
What is a shape called if it has 100 sides?
Comment on Aditri Mallick's post “What is a shape called if...”
(18 votes)
- Axelotl_Hotshot
  Posted a year ago. Direct link to Axelotl_Hotshot's post “For short, it can be a 10...”
  For short, it can be a 100-gon, but it is called zocchihedron.
  Comment on Axelotl_Hotshot's post “For short, it can be a 10...”
  (9 votes)
James Blagg✝
Posted 3 years ago. Direct link to James Blagg✝'s post “Can something have a diff...”
Can something have a different amount of sides and corners? Like 4 sides and 5 corners?
Comment on James Blagg✝'s post “Can something have a diff...”
(12 votes)
- Rei the Orthworm
  Posted 2 years ago. Direct link to Rei the Orthworm's post “accutually, a 'v' has two...”
  accutually, a 'v' has two sides and one corner. Open shapes will have a different number of sides and corners, closed shapes will not.
  (6 votes)
TSLAMeganHalili
Posted 9 years ago. Direct link to TSLAMeganHalili's post “Are there any other diffe...”
Are there any other differences between an oval and a circle (or is the length the only difference)?
Comment on TSLAMeganHalili's post “Are there any other diffe...”
(0 votes)
- Barrett Southworth
  Posted 9 years ago. Direct link to Barrett Southworth's post “An oval is a circle that ...”
  An oval is a circle that is elongated in some direction. A circle could be elongated by no value at all so this holds.
  All circles are ovals
  Not all Ovals are circles
  Comment on Barrett Southworth's post “An oval is a circle that ...”
  (14 votes)
khoo46090
Posted 9 years ago. Direct link to khoo46090's post “I've always thought corne...”
I've always thought corners meant where two lines meet at a 90 degree angle, but is it really just where two lines meet together? Mainly I'm asking about at
2:57
and at
2:06
.
(3 votes)
- ViseanTourist
  Posted 9 years ago. Direct link to ViseanTourist's post “In shapes, a corner is an...”
  In shapes, a corner is any place at which two lines meet. In real life, you most often encounter corners that are parts of rooms, or tables, and those should be 90 degrees. Hope this helps!
  Comment on ViseanTourist's post “In shapes, a corner is an...”
  (3 votes)
Justin Railey
Posted 9 years ago. Direct link to Justin Railey's post “Whats the difference betw...”
Whats the difference between a circle and a oval?
Comment on Justin Railey's post “Whats the difference betw...”
(3 votes)
- Barrett Southworth
  Posted 9 years ago. Direct link to Barrett Southworth's post “An oval is slightly round...”
  An oval is slightly rounded or elongated, might be an ellipse, might be a circle too if it is the same shape as a circle. A circle is completely round, all the edges are the same distance away from the center. So an oval can be longer along one side than another.
  Comment on Barrett Southworth's post “An oval is slightly round...”
  (3 votes)
The Professor
Posted 9 years ago. Direct link to The Professor's post “Could there be a shape th...”
Could there be a shape that has one side and one corner?
(3 votes)
- William Carroll
  Posted 9 years ago. Direct link to William Carroll's post “There could not be a shap...”
  There could not be a shape with one side and one corner for two reasons.
  
  1. The first criteria for a shape is closed. It would not be possible to close a figure with one side.
  
  2. A figure with one side cannot form a corner. This is because a corner is formed by two sides.
  
  I hope this helps!
  
  Bill
  Comment on William Carroll's post “There could not be a shap...”
  (2 votes)
Djouhra Adjerit
Posted 9 years ago. Direct link to Djouhra Adjerit's post “"A trapezoid is a 4-sided...”
"A trapezoid is a 4-sided flat shape with straight sides that has a pair of opposite sides parallel".
Does that mean that squares and rectangles are trapezoids ?
(1 vote)
- Lena
  Posted 9 years ago. Direct link to Lena's post “A trapezoid cannot be a s...”
  A trapezoid cannot be a square because a square have 2 pairs of parallel sides while a trapezoid only has one pair. In this case, a rectangle cannot be a trapezoid either.
  (5 votes)
Rasmus R
Posted 8 years ago. Direct link to Rasmus R's post “Is there any difference b...”
Is there any difference between an oval and an ellipse?
(2 votes)
- Ben Willetts
  Posted 8 years ago. Direct link to Ben Willetts's post “Yes, there is. An ellips...”
  Yes, there is. An ellipse is a precisely-defined mathematical figure, which has two axes of symmetry. Its shape is defined by two numbers, called the semi-major and semi-minor axes (the equivalents of the radius of a circle). The term "oval", by contrast, does not have a precise meaning, and is used for any shape which resembled an egg, with either one or two axes of symmetry.
  (2 votes)

Video transcript

- [Voiceover] Oh look, it's my cousin Fal! Cousin Fal, what can I do for you? - [Voiceover] Hey Sal, what's up? - [Voiceover] Oh, well not much, I'm just sitting here thinking about what video I should do next. - [Voiceover] Well then maybe you can help me. I'm starting a shape collection. - [Voiceover] Okay, so how do you need help? - [Voiceover] Well look at these shapes over here! I have no way to classify them! - [Voiceover] Okay, well there's a bunch of ways that you could classify them. The first way, you could think about how many sides each of these shapes have, so that's one way to think about it, how many sides they have. - [Voiceover] How do I figure that out? - [Voiceover] Okay, well let's look at each of these and think about how many sides they have. So this first shape right over here this is one side. We see this kind of straight right over here, it's the straight line between these two corners, so that's one side. Two sides, three sides, and four sides. So this shape right over here has four sides. - [Voiceover] Okay, I think I get it. What about this shape right over here? - [Voiceover] Okay,well let's see. This one, well same idea, this one also looks like it has one, two, three, and four. Four sides. - [Voiceover] What about this one? - [Voiceover] Okay, well this one, actually this is interesting. This one actually had no corners, and it has no sides, there's no straight edges over here, this thing is all curved. So since it has no corners, it also has no sides, or at least the way that I'm thinking about it. So I would say that this one over here has zero sides. Let me write that a little bit neater for you. - [Voiceover] Okay yeah, I like to write things really neat. - [Voiceover] Okay, zero sides. And it has zero corners. Actually let me write them for all of them. This one has four sides, and we could also count the corners. We have one, that's where the two sides meet. One, two, three, four corners. This shape over here, it also has four sides, we already counted that and it has one, two, three, four corners. So four sides and four corners actually describes both of these shapes, this one has zero sides and zero corners-- - [Voiceover] What about the green one? - [Voiceover] Okay, well let's just see. One side, two sides, three sides, and four sides, and it also has one, two, three, four corners. So this is also four sides and four corners is also true of that one there. - [Voiceover] Do all shapes have four sides and four corners? - [Voiceover] No no, not at all. I mean this one right over here had zero sides and zero corners, and actually this last shape right over here, doesn't seem to have four sides or four corners. If we count them, we have one side, two sides, and three sides. So this one has three sides, and if we count the corners we have one corner, two corners, and three, and three corners. - [Voiceover] Oh, thanks a bunch Uncle-- Cousin Sal. But I always get confused whether you're my cousin or my uncle. But I'll call you Cousin Sal. But I read in a shape magazine that there was other ways that I can classify. I can classify based on whether the sides have the same size. So which of these have all the sides are the same size? - [Voiceover] Okay, well calm down. Let's look at this. So if you look at this one, it has four sides. But we see, that this side right over here, this green side, is clearly shorter than this purple side. So all the four sides here are not the same length. But if we look at this shape right over here, this side at least looks like the same length as this side. And that looks like the same length as this side, and that looks like the same length as that side. So it looks over here like all four sides are the same length. And that's also true for this shape. This side looks the same length as that side, looks the same length as that side, looks the same length as that side. That's also true for this three-sided shape. This side looks the same length as that side, This is the same length as that one. - [Voiceover] Oh, thank you so much Cousin Sal! I'm ready to go classify my shape collection. This is awesome! - [Voiceover] Well I'm glad that I could help!