Question 1008225
{{{x^2+4x+y^2-6y=-k}}}
{{{x^2+4x+4+y^2-6y+9=-k+4+9}}}
{{{(x+2)^2+(y-3)^2=13-k}}}


Radius of 5 means radius squared is  25;
{{{13-k=25}}}
{{{-k=25-13}}}
{{{highlight(k=-12)}}}