How to find the CENTER AND RADIUS of a circle (KristaKingMath)

If we have the equation of a circle, we can easily find its center point and the radius of the circle by manipulating the equation until it's in standard form for the equation of a circle.

Once the equation is in standard form, we can identify the center of the circle as the point (h,k), and the radius of the circle as r, which is just the square root of the constant on the right side of the equation (assuming the equation is already in standard form!).

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Hi, I’m Krista! I make math courses to keep you from banging your head against the wall. ;)

Math class was always so frustrating for me. I’d go to a class, spend hours on homework, and three days later have an “Ah-ha!” moment about how the problems worked that could have slashed my homework time in half. I’d think, “WHY didn’t my teacher just tell me this in the first place?!”

[vrendus]

In my summer math program.I would like to see your sewing arts.You know how to make complex weaves.Thank you good vid

[hepxyaoi]

So what if the equation is
X squared + y squared = 25
What is the center and the radius?

[demonarkus]

What if the equation is y=x^2-16x+128 and the given radius is 4square root of 2?

[sincity]

I didn’t get why the radius is a square

[rajveerkaur]

Kindly do find the centre of circle ( x)(x)+(y)(y)=9

[edjayee]

The radius would be 5 not square root of 5, since you squared the square root of five they cancel out leaving 5 as the answer

[BobP]

Although unfamiliar with the Reminder equation, I can follow the equations. And that the radius end is the center of the circle. But what do the points h=-1, and k=0 mean. 
Better still, where do I find the Reminder equations? 
P.S. Is there a person with a name that voice belongs to? A nickname, alias, Siri?

[Unidentifying]

i thought that was funny for some odd reason, maybe its just me