00:01
The final equation of a circle in standard form is x minus h squared plus y minus k squared equals r squared where the point h k is the center of the circle and r is the radius.
00:17
So take for example the equation x squared plus y minus three squared equals 49.
00:28
Now we want to know the center and the radius of the surface of the circle.
00:34
So the center is the point hk.
00:40
Now looking at this, our x term, it's only x squared instead of x minus h squared.
00:46
So x squared is the same as x minus 0 squared.
00:52
So we know that our h is 0 and our k is 3.
00:58
So the center of the circle is at 0 3.
01:01
Our radius is r and r squared is 49.
01:06
So the square root of 49 is 7.
01:08
So we know our radius is 7.
01:11
Grathing this circle, we would start by first plotting our central point.
01:16
So 03, it's right there...