Question 753098
{{{x^2+y^2+12x-22y+13=0 }}}

{{{(x^2+12x)+(y^2-22y)+13=0 }}}...complete the square

{{{(x^2+12x+__)-___+(y^2-22y+____)-___+13=0 }}}     

{{{(x^2+12x+36)-36+(y^2-22y+121)-121+13=0 }}}

{{{(x+6)^2+(y-11)^2-121-36+13=0 }}}

{{{(x+6)^2+(y-11)^2-144=0 }}}

{{{(x+6)^2+(y-11)^2=144 }}}

{{{(x+6)^2+(y-11)^2=12^2 }}}.......the center is at ({{{-6}}},{{{11}}}) and radius {{{r=12}}}


{{{drawing( 600, 600, -20, 15, -5, 20,
  grid( 1 ),circle(-6,11,0.2),
  circle( -6, 11, 12 )
  
)}}}