A geometry problem by A Former Brilliant Member

${ x }^{ 2 }-x+\frac { 1 }{ 4 } ={ \left( x-\frac { 1 }{ 2 } \right) }^{ 2 }$ and ${ y }^{ 2 }+2y+1={ \left( y+1 \right) }^{ 2 }$ Then ${ \left( x-\frac { 1 }{ 2 } \right) }^{ 2 }+{ \left( y+1 \right) }^{ 2 }-\frac { 9 }{ 4 } =0$ is the same as the original expression. Then 9/4 is the square of the radius.

You asked for the answer correct to 5 decimal places but you gave the answer to 3 decimal places.