Question

Radius of a circle formula of general equation

Answer 1

$2\pi r \: i \: hope \: so \: that \: is \: the \: answer$

Answer 2

${x}^{2} + {y}^{2} + 2gx + 2fy + c = 0$
Radius of this circle is
$\sqrt{ {g}^{2} + {f}^{2} - c }$