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Original poster

How many sides does a circle have?

166 replies

Ravingstarfish · 30/05/2019 12:16

Just that really. My sons tutor has taught him this and several people have said she’s wrong.... so how many sides does a circle have?

OP posts:
Original poster
Ravingstarfish · 30/05/2019 12:29

Well done those who said 1!
Tutor has taught him 1, he was insistent it was 0. I’m sure at school I was taught 0 but glad I’m not the only one who wasn’t sure Smile

OP posts:
Aragog · 30/05/2019 12:32

1 continuous side, 0 vertices

floraloctopus · 30/05/2019 12:34

One curved edge, no sides

newdocket · 30/05/2019 12:36

side as in face? then 2

mynamechangemyrules · 30/05/2019 12:37

It has to have one side or it wouldn't be there, surely..?!

I've taught about 600 kids that it has one so let's hope that's the right answer Grin

MaidofKent78 · 30/05/2019 12:38

Technically it's not a shape; it's a locus where every point on the circumference is the same distance (radius) from the centre

calpop · 30/05/2019 12:38

1 egde 0 sides

calpop · 30/05/2019 12:40

or maybe 0 edges 1 side

Bythebeach · 30/05/2019 12:40

I thought it was infinite from extrapolation from a regular polygon??

SeeWhoRustsFirst · 30/05/2019 12:42

Why does a side/edge have to be straight? Answer's a clear-cut "1" as far as I'm concerned. For the same reason, a semi-circle has two. If you think a circle has no/two/infinite sides, how many do you think a semi circle has?!

DontCallMeShitley · 30/05/2019 12:57

2 sides, inside and outside.

TooTrueToBeGood · 30/05/2019 13:01

I was taught 1 but does it really matter? If you know what a circle is then it's just pedsntics arguing whether it has an edge, a side or neither. If you don't know what a circle is you probably don't know what a side or an edge is either.

LadyRannaldini · 30/05/2019 13:01

The inside and the outside. So 2?

By that 'logic' all plane figures have 2 sides, inside and out.
I think there is confusion here about sides and faces. A circles has 1 curved edge (side) and 1 face.

floraloctopus · 30/05/2019 13:27

It has to have one side or it wouldn't be there, surely..?!

Sides are faces though so it has to have those. The problem is people interchangeably use faces, edges and sides

NCasVOuting · 30/05/2019 13:45

In the maths curriculum, it's 1.

NotWithTheProgramme · 30/05/2019 14:03

Sitting here feeling really stupid and secretly very glad that DH takes the maths homework questions while I deal with English...

mangomama91 · 30/05/2019 14:04

1

NoBaggyPants · 30/05/2019 14:17

A circle has one side.

An apeirogon has infinite sides and looks very much like a circle, but is not.

Explained well in this video:

m.youtube.com/watch?v=dUiEyD_ThwM

JAPAB · 30/05/2019 14:39

Echoing others. A circle is the limit of a regular n-gon as n tends to infinity. But that is not the same as saying that it is an infinite n-gon.

It has no sides in the sense of having straight lines making up its circumference. Or at least that is my understanding.

Drogosnextwife · 30/05/2019 14:42

I was definitely taught 1 at school, because there is one line but no corners.

JAPAB · 30/05/2019 15:12

I was definitely taught 1 at school, because there is one line but no corners.

Problem is, every shape has one side if you ignore thingds like edges, vertices, and just go by the fact that it has an unbroken boundary line all around it :)

Puppytooth · 30/05/2019 15:57

Oh dear I would have said two sides as in two faces. A sphere on the other hand would have....ummmm....1?.....0?.....hmmm Blush

Drogosnextwife · 30/05/2019 18:56

Problem is, every shape has one side if you ignore thingds like edges, vertices, and just go by the fact that it has an unbroken boundary line all around it smile

🤷‍♀️ But the answer is one isn't it? so....

Chickenwing · 30/05/2019 19:05
AltheaVestr1t · 30/05/2019 19:40

A circle doesn’t have any faces, only 3D shapes have faces. By definition, a side is one of the line segments of a polygon, which is a shape made up of only straight sides. A circle has one curved edge, and no sides.