\[ a y'(x)^2+b y(x)+y''(x)=0 \] ✓ Mathematica : cpu = 0.591465 (sec), leaf count = 104
\[\left \{\left \{y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}-\frac {\sqrt {2} a}{\sqrt {2 e^{-2 a K[1]} c_1 a^2-2 b K[1] a+b}}dK[1]\& \right ][x+c_2]\right \},\left \{y(x)\to \text {InverseFunction}\left [\int _1^{\text {$\#$1}}\frac {\sqrt {2} a}{\sqrt {2 e^{-2 a K[2]} c_1 a^2-2 b K[2] a+b}}dK[2]\& \right ][x+c_2]\right \}\right \}\] ✓ Maple : cpu = 1.332 (sec), leaf count = 79
\[\left \{-c_{2}-x +\int _{}^{y \left (x \right )}-\frac {2 a}{\sqrt {4 c_{1} a^{2} {\mathrm e}^{-2 \textit {\_a} a}-4 \textit {\_a} a b +2 b}}d \textit {\_a} = 0, -c_{2}-x +\int _{}^{y \left (x \right )}\frac {2 a}{\sqrt {4 c_{1} a^{2} {\mathrm e}^{-2 \textit {\_a} a}-4 \textit {\_a} a b +2 b}}d \textit {\_a} = 0\right \}\]