\[ y'(x)=\frac {3 a^2 b x y(x)^2+2 a^2 b x y(x)+a^3 y(x)^3+a^3 y(x)^2+a^3+3 a b^2 x^2 y(x)+a b^2 x^2+b^3 x^3}{a^3} \] ✓ Mathematica : cpu = 0.333847 (sec), leaf count = 145
\[\text {Solve}\left [-\frac {1}{3} (29 a+27 b)^{2/3} \text {RootSum}\left [\text {$\#$1}^3 (29 a+27 b)^{2/3}-3 \text {$\#$1} a^{2/3}+(29 a+27 b)^{2/3}\& ,\frac {\log \left (\frac {\frac {a+3 b x}{a}+3 y(x)}{\sqrt [3]{\frac {29 a+27 b}{a}}}-\text {$\#$1}\right )}{a^{2/3}-\text {$\#$1}^2 (29 a+27 b)^{2/3}}\& \right ]=\frac {1}{9} x \left (\frac {29 a+27 b}{a}\right )^{2/3}+c_1,y(x)\right ]\] ✓ Maple : cpu = 0.296 (sec), leaf count = 42
\[ \left \{ y \left ( x \right ) ={\frac {{\it RootOf} \left ( \int ^{{\it \_Z}}\! \left ( {{\it \_a}}^{3}a+{{\it \_a}}^{2}a+a+b \right ) ^{-1}{d{\it \_a}}a-x+{\it \_C1} \right ) a-bx}{a}} \right \} \]