Question

What is Equation of circle?

Answer

Equation of circle is a y is the radius and (h, k) is the center then the equation of such a circle is ${\left(x-h\right)}^2+{\left(y-k\right)}^2=y^2$
$\mathrm{or }{x}^2+y^2+\alpha x+\beta y+y=0$
$\mathrm{in\; which }\alpha =-2$
$\beta =-2k$
$\gamma \; =h^2+k^2-y^2$