Question 1115590
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<pre>
{{{(x^2-4x)}}} + {{{(y^2+12y)}}} - {{{20}}} = {{{0}}}

{{{(x^2-4x+4)}}} + {{{(y^2+12y+36)}}} = {{{20+4+36}}}

{{{(x-2)^2}}} + {{{(y+6)^2}}} = {{{60}}}

Circle centered at ({{{2}}},{{{-6}}}) with a radius of {{{R}}} = {{{sqrt(60)}}} = {{{2*sqrt(15)}}}
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