\[ \boxed { 2\, \left ( {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) \right ) y \left ( x \right ) - \left ( {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) \right ) ^{2}+ \left ( ay \left ( x \right ) +bx \right ) \left ( y \left ( x \right ) \right ) ^{2}=0} \]
Mathematica: cpu = 1.244158 (sec), leaf count = 36 \[ \text {DSolve}\left [y(x)^2 (a y(x)+b x)+2 y(x) y''(x)-y'(x)^2=0,y(x),x\right ] \]
Maple: cpu = 1.638 (sec), leaf count = 0 \[ \text {could not solve} \]