\[ y'(x)=\frac {x^6+9 x^4 y(x)-6 x^3+27 x^2 y(x)^2-18 x y(x)+27 y(x)^3-18 x}{9 x^2+27 y(x)+27} \] ✓ Mathematica : cpu = 0.170973 (sec), leaf count = 75
DSolve[Derivative[1][y][x] == (-18*x - 6*x^3 + x^6 - 18*x*y[x] + 9*x^4*y[x] + 27*x^2*y[x]^2 + 27*y[x]^3)/(27 + 9*x^2 + 27*y[x]),y[x],x]
\[\left \{\left \{y(x)\to \frac {1}{3} \left (-x^2-3\right )+\frac {1}{27 \left (\frac {1}{27}-\frac {1}{\sqrt {-1458 x+c_1}}\right )}\right \},\left \{y(x)\to \frac {1}{3} \left (-x^2-3\right )+\frac {1}{27 \left (\frac {1}{27}+\frac {1}{\sqrt {-1458 x+c_1}}\right )}\right \}\right \}\] ✓ Maple : cpu = 0.04 (sec), leaf count = 77
dsolve(diff(y(x),x) = (-18*x*y(x)-6*x^3-18*x+27*y(x)^3+27*x^2*y(x)^2+9*y(x)*x^4+x^6)/(27*y(x)+9*x^2+27),y(x))
\[y \left (x \right ) = \frac {-2 c_{1} x^{2}+2 x^{3}+3 \sqrt {2 c_{1}-2 x +1}+3}{-6 x +6 c_{1}}\]