$${ x }^{ 2 } + { y }^{ 2 } -4x-6y-3=0$$
$x=\sqrt{-\left(y-7\right)\left(y+1\right)}+2$
$x=-\sqrt{-\left(y-7\right)\left(y+1\right)}+2$
$y=\sqrt{-\left(x-6\right)\left(x+2\right)}+3$
$y=-\sqrt{-\left(x-6\right)\left(x+2\right)}+3$
$x=\sqrt{\left(7-y\right)\left(y+1\right)}+2$
$x=-\sqrt{\left(7-y\right)\left(y+1\right)}+2\text{, }y\geq -1\text{ and }y\leq 7$
$y=\sqrt{\left(6-x\right)\left(x+2\right)}+3$
$y=-\sqrt{\left(6-x\right)\left(x+2\right)}+3\text{, }x\geq -2\text{ and }x\leq 6$