Angle measurement and circle arcs | Angles and intersecting lines | Geometry | Khan Academy

Did you know that the measurement of an angle is related to the arc of a circle? Yes, indeed! Watch.

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Geometry on Khan Academy: We are surrounded by space. And that space contains lots of things. And these things have shapes. In geometry we are concerned with the nature of these shapes, how we define them, and what they teach us about the world at large--from math to architecture to biology to astronomy (and everything in between). Learning geometry is about more than just taking your medicine ("It's good for you!"), it's at the core of everything that exists--including you. Having said all that, some of the specific topics we'll cover include angles, intersecting lines, right triangles, perimeter, area, volume, circles, triangles, quadrilaterals, analytic geometry, and geometric constructions. Wow. That's a lot. To summarize: it's difficult to imagine any area of math that is more widely used than geometry.

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[bread]

Dude I am 14 years old and after literal years of not knowing how these worked the man taught me. Give him an award.

[zerohero]

thank you so much my teacher his is name is mondragon sucks and you help me when i watch video i learn more then in that class

[dylanmn]

Thank you so much. I learned a lot from this video.

[yoo]

Could you maybe post one or two videos a day? I appreciate that you are putting out so much content but I cannot watch it all and it is clogging up my sub box. I do understand that math is very diverse and that you are trying to cover every concept in existence. Although your videos are very helpful, it has become hard to find other videos among the Khan Academy ones.

[TT-czpr]

can't you explain this theorm the measure of the angle formed by the lines of two chords intersecting outside a circle is half the difference of the measure of the arc they intercept. it's would be really helpful please explain this

[tiffanylol]

We can all agree, *we don’t want to watch this*

[annejohnson]

Anybody else's teacher told them to watch this?lol

[helloluvie]

how to know that is 3/4 or something ???


pls answer me i need ur help

[Kozzly]

my man, i need the lesson, not the story of the number 360

[onebeets]

so angles start on the right and are measured counterclockwise
*i see*

[literallygrass]

I swear, this guy doesnt have emotion

[wanafly]

you guessed at the 1/6. exact measurement please. all the other examples were child's play.

[gamerhub]

lets make a circle him :copy paste circle be fore video

[jodenial]

anyone else think he sounds like Dwayne(The Rock)Johnson

[Galactic-ed]

maybe it came from how many 10 seconds there is a hour 360 degrees

[leonolivier]

I have a 8 year daughter and you just taught her absolutely nothing! Yes, me and you know to "let's say this is 1/6 or 1/4." But she doesn't and you have to logical explain how that's a fact! By saying "let's say" that in itself is referring to a "guess". You started off good with 360 degrees. That's more of a fact and a building block. But now for all the dummies in the room, how you figure 1/6 without a protractor? This is why many people struggle in math! It's like trying to teach something somebody made up out of thin air. Or like the concept of once you start a lie you have to continue a lie. What we here playing the guessing game? Otherwise we just memorizing angles like math flash cards. Smh math is a joke