\[ (x-y(x)) y''(x)+\left (-y'(x)-1\right ) \left (y'(x)^2+1\right )=0 \] ✓ Mathematica : cpu = 2.2049 (sec), leaf count = 75
\[\left \{\left \{y(x)\to -\sqrt {-x^2-2 c_2 x+e^{2 c_1}-c_2{}^2}-c_2\right \},\left \{y(x)\to \sqrt {-x^2-2 c_2 x+e^{2 c_1}-c_2{}^2}-c_2\right \}\right \}\] ✓ Maple : cpu = 1.856 (sec), leaf count = 105
\[\left \{y \left (x \right ) = x +\RootOf \left (c_{2}-x +\int _{}^{\textit {\_Z}}\frac {c_{1}^{2} \textit {\_f}^{2}-1}{-c_{1}^{2} \textit {\_f}^{2}+c_{1} \sqrt {-c_{1}^{2} \textit {\_f}^{2}+2}\, \textit {\_f} +2}d \textit {\_f} \right ), y \left (x \right ) = x +\RootOf \left (c_{2}-x +\int _{}^{\textit {\_Z}}-\frac {c_{1}^{2} \textit {\_f}^{2}-1}{c_{1}^{2} \textit {\_f}^{2}+c_{1} \sqrt {-c_{1}^{2} \textit {\_f}^{2}+2}\, \textit {\_f} -2}d \textit {\_f} \right )\right \}\]