\[ \boxed { {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) =-{\frac {-y \left ( x \right ) +{x}^{3}\sqrt { \left ( y \left ( x \right ) \right ) ^{2}+{x}^{2}}-{x}^{2}\sqrt { \left ( y \left ( x \right ) \right ) ^{2}+{x}^{2}}y \left ( x \right ) }{x}}=0} \]
Mathematica: cpu = 0.124516 (sec), leaf count = 111 \[ \left \{\left \{y(x)\to \frac {x \left (-2 e^{\sqrt {2} c_1+\frac {\sqrt {2} x^3}{3}}+e^{2 \sqrt {2} c_1+\frac {2 \sqrt {2} x^3}{3}}-1\right )}{2 e^{\sqrt {2} c_1+\frac {\sqrt {2} x^3}{3}}+e^{2 \sqrt {2} c_1+\frac {2 \sqrt {2} x^3}{3}}-1}\right \}\right \} \]
Maple: cpu = 0.156 (sec), leaf count = 49 \[ \left \{ \ln \left ( 2\,{\frac {x \left ( \sqrt {2\, \left ( y \left ( x \right ) \right ) ^{2}+2\,{x}^{2}}+y \left ( x \right ) +x \right ) }{y \left ( x \right ) -x}} \right ) +{\frac {\sqrt {2}{x}^{3}}{3}}-\ln \left ( x \right ) -{\it \_C1}=0 \right \} \]