$$\left. \begin{array} { l } { x ^ { 2 } - 4 y ^ { 2 } - 2 x + 16 y - 40 = 0 } \end{array} \right.$$
$x=\sqrt{4y^{2}-16y+41}+1$
$x=-\sqrt{4y^{2}-16y+41}+1$
