Radius and center for a circle equation in standard form | Algebra II | Khan Academy

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[thomass]

Who else wishes Khan was your actual math professor ??

[carrollsteiner]

Who would have thought the COVID-19 would find me re-visiting high school years of memories? The math I was comfortable with has slipped into the never land of forgetfulness....! Thank you.

[jadem.]

I like how he explains the why the values at the end.

[alejndraalmirowitsch]

when i realized that distance formula and circle equation thingy are just complication of pythagorean theorem, i'm so glad.

[Paaaaaks]

Now i get it, thank you for the explanation :D.

[KYRGarage]

he nail that circle ngl, good stuff mr. khan

[lime]

*what if my sf= x2+y2 = 20 how am i going to solve for the center?*

[francesbrown]

Ushio your (x, y) if that is the center that is what he is using (h, k) for. You would also have to have the radius to complete the equation. 

[richardroulstone]

Another great video guys. Thanks as always for making things clear and easy to understand. And organic chemistry too!

[mahendrargosavibharti]

I need various form of circle... lesson is equation of circle

[gabrieldiaz]

I love how he has over 2, 000, 000 subscribers yet doesn't get over 200 likes...or even over 700, 000 views hmmm

[shaquille_oatmeal]

"what is the center of this equation and its radius?"
normal person: (-3, 4), 7




khan: let's remind ourselves what a circle

[blueskies]

what do you do I one of the points is negative

[priscillalopez]

What if they don't give you the equation

[pres]

aww but I need how to get the form from two points. So they give me (x, y)

[idkanymore]

I don’t understand he didn’t even do anything with the 49 how am I supposed to get the number of units

[xogmaster]

Is it just me or did he mess up where he threw in (-3) as the value for h? In fact he goes over it and says 'Well what if this negative 3 was a positive 3, but it's not, so it's minus negative three" uhh.. that looks like a +3 to me

[imannasseri]

You sound exactly like elliot from strength camp on youtube

[revinger]

للأسف يبغالنا نترجم زي هذه المقاطع للعربية

[adrianjohnson]

Bro non of this matters this is a waste of my time and yours none of us will be using any of this in the next 15 years of our lives