Radius of center (0,3) = 1

Let the center of C be (x, y) and the radius be | y |.

Under the root symbol [x? +(y-3)？ ]= 1+|y|

x？ -6y+9= 1+2|y|

If y>0 is x? -6y+9= 1+2y 8y=x？ +8

If y < 0 is x? -6y+9= 1-2y 4y=x？ +4