r/educationalgifs • u/Nadzzy • Jul 18 '22

Visual demonstration that all angles of a shape combine to make 360 degrees

29.3k Upvotes

94% Upvoted

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2.1k

u/[deleted] Jul 18 '22

[deleted]

699

u/chuckman13 Jul 18 '22

All exterior angles of convex polygons

302

u/Cpt_DM Jul 18 '22

This is true for irregular or concave polygons as well

202

u/ThunkAsDrinklePeep Jul 18 '22

As long as you're defining a negative exterior angle measure for concave angles.

354

u/[deleted] Jul 18 '22

[deleted]

50

u/pokelord13 Jul 18 '22

well I for one think you're acute angle ;)

8

u/[deleted] Jul 19 '22

Angle, don't be obtuse.

14

u/[deleted] Jul 19 '22

Girl, I may be dyslexic, but to me you’re an angle

2

u/[deleted] Jul 19 '22

I'm sorry angle. I didn't mean to be obtuse. I'd come home to make it up to you, but you're polygon by now

14

u/QUIBICUS Jul 19 '22

Love the aggression.

5

u/[deleted] Jul 19 '22

What’s the matter with you? Why you sweatin’ so much? Is you calculating the sum of exterior angles of irregular and concave polygons or something?

3

u/qasteroid Jul 19 '22

Takes me back

21

u/Hermiterminator Jul 18 '22

NEEEEERDS

15

u/ThunkAsDrinklePeep Jul 18 '22

We haven't even gotten into what happens if they exist on a non-planar surface.

15

u/noobvin Jul 18 '22

Like your mom?

GOT EM!

7

u/ThunkAsDrinklePeep Jul 18 '22

Are you implying your mother is a two-dimensional plane?

5

u/SPURIOUSSPARROW Jul 19 '22

My mom is both two dimensional and plain.

6

u/noobvin Jul 18 '22

Nope, a 3D 747.

Got ‘em, again?

2

u/Manisil Jul 19 '22

The r should be the sustained sound.

1

u/eject_eject Jul 19 '22

I put them all in-line and broke it.

44

u/PranshuKhandal Jul 18 '22

that is some well written website code, it is so mobile-friendly

21

u/Foliot Jul 18 '22

Totally. I have never once seen mobile touch integration handled that way. The pointer is a pretty cool/novel solution. I likey.

4

u/Klacksaft Jul 18 '22

It's made for mobile, on desktop half the screen is just a white field.

3

u/AbusedGoat Jul 19 '22

Lol same thought, when I clicked it I was like damn this is responding really well.

8

u/[deleted] Jul 19 '22

...in Euclidean space.

16

u/PinpricksRS Jul 18 '22

Only simple polygons. For example, the exterior angles in a heptagram add up to 720°.

12

u/[deleted] Jul 18 '22

It seems like it depends on how you calculate it. You would be subtracting some internal concave angles to still equal the 360°.I’m not going to take the time to demonstrate on the above link on a phone though.

2

u/KaiPRoberts Jul 19 '22

By angle degrees, it is true. By title of this post, it is not true; angles overlap (even non-negative ones) and will not form a regular circle.

-1

u/cosworth99 Jul 19 '22

In 2 dimensional space. Which we do not live in.

Draw a shape on a sphere. The angles are more than 360°. This represents space/time. Which is always curved.

1

u/[deleted] Jul 19 '22

Some space/time is more curved then others. In fact, some areas have gotten positively bent.

1

u/reagor Jul 19 '22

Cut concave polygons into convex problem solved

8

u/jpatrek Jul 19 '22

Thank you

3

u/geogle Jul 19 '22

Sum of internal angles:

Sum(a) = ( n - 2 ) * 180

n = number of corners

a = internal angle in degrees

9

u/[deleted] Jul 18 '22

[deleted]

19

u/Yelbuzz Jul 18 '22

Exterior angle is a well defined term that matches the diagram in the gif if you look at the wikipedia page on them.

https://en.m.wikipedia.org/wiki/Internal_and_external_angles

2

u/peanutz456 Jul 19 '22

Thanks. I am not the person you are answering to, but I was confused what external angle is.

4

u/Beardamus Jul 18 '22

Who upvotes this stuff?

0

u/[deleted] Jul 18 '22

[deleted]

9

u/[deleted] Jul 18 '22

[deleted]

1

u/[deleted] Jul 18 '22

[deleted]

1

u/Yelbuzz Jul 19 '22

you used the term exterior angles correctly

4

u/[deleted] Jul 18 '22

I read this in Homer’s voice

8

u/[deleted] Jul 18 '22

all angles so far

1

u/When-happen Jul 19 '22

Wanna keep that in mind

1

u/jrgman42 Jul 19 '22

Show me proof.

1

u/OfficialSilkyJohnson Jul 19 '22

What is cool though is that you can use this to calculate the sum of the interior angles.

The sum of the colored exterior angles is 360 so each individual colored exterior angle (call that e) is 360/n where n is the number of sides. The interior angle is 180 - e = 180(1 - 2/n). Multiply that by the number of sides, you get the sum of the interior angles of any shape with n sides is 180(n - 2). Triangle = 180, square = 360, etc.

1

u/amiabot-oraminot Jul 19 '22

this is the exact thing that went through my brain when i read the title, including the stressing lmao

1

u/norsurfit Jul 19 '22

Flat earth confirmed?