\[ y'(x)=\frac {-a^2-a b y(x)-a b \sqrt {x}+a b+b^2 x+b^2}{a \left (a (-y(x))-a \sqrt {x}+a+b x+b\right )} \] ✓ Mathematica : cpu = 0.13143 (sec), leaf count = 607
\[\left \{\left \{y(x)\to \frac {\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 e^{12 c_1}+16 x^3\right )-\frac {24 \text {$\#$1}^4 x^2}{a^4}+\frac {8 \text {$\#$1}^3 x^{3/2}}{a^6}+\frac {9 \text {$\#$1}^2 x}{a^8}-\frac {6 \text {$\#$1} \sqrt {x}}{a^{10}}+\frac {1}{a^{12}}\& ,1\right ]}+a \left (a \left (-\sqrt {x}\right )+a+b x+b\right )}{a^2}\right \},\left \{y(x)\to \frac {\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 e^{12 c_1}+16 x^3\right )-\frac {24 \text {$\#$1}^4 x^2}{a^4}+\frac {8 \text {$\#$1}^3 x^{3/2}}{a^6}+\frac {9 \text {$\#$1}^2 x}{a^8}-\frac {6 \text {$\#$1} \sqrt {x}}{a^{10}}+\frac {1}{a^{12}}\& ,2\right ]}+a \left (a \left (-\sqrt {x}\right )+a+b x+b\right )}{a^2}\right \},\left \{y(x)\to \frac {\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 e^{12 c_1}+16 x^3\right )-\frac {24 \text {$\#$1}^4 x^2}{a^4}+\frac {8 \text {$\#$1}^3 x^{3/2}}{a^6}+\frac {9 \text {$\#$1}^2 x}{a^8}-\frac {6 \text {$\#$1} \sqrt {x}}{a^{10}}+\frac {1}{a^{12}}\& ,3\right ]}+a \left (a \left (-\sqrt {x}\right )+a+b x+b\right )}{a^2}\right \},\left \{y(x)\to \frac {\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 e^{12 c_1}+16 x^3\right )-\frac {24 \text {$\#$1}^4 x^2}{a^4}+\frac {8 \text {$\#$1}^3 x^{3/2}}{a^6}+\frac {9 \text {$\#$1}^2 x}{a^8}-\frac {6 \text {$\#$1} \sqrt {x}}{a^{10}}+\frac {1}{a^{12}}\& ,4\right ]}+a \left (a \left (-\sqrt {x}\right )+a+b x+b\right )}{a^2}\right \},\left \{y(x)\to \frac {\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 e^{12 c_1}+16 x^3\right )-\frac {24 \text {$\#$1}^4 x^2}{a^4}+\frac {8 \text {$\#$1}^3 x^{3/2}}{a^6}+\frac {9 \text {$\#$1}^2 x}{a^8}-\frac {6 \text {$\#$1} \sqrt {x}}{a^{10}}+\frac {1}{a^{12}}\& ,5\right ]}+a \left (a \left (-\sqrt {x}\right )+a+b x+b\right )}{a^2}\right \},\left \{y(x)\to \frac {\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 e^{12 c_1}+16 x^3\right )-\frac {24 \text {$\#$1}^4 x^2}{a^4}+\frac {8 \text {$\#$1}^3 x^{3/2}}{a^6}+\frac {9 \text {$\#$1}^2 x}{a^8}-\frac {6 \text {$\#$1} \sqrt {x}}{a^{10}}+\frac {1}{a^{12}}\& ,6\right ]}+a \left (a \left (-\sqrt {x}\right )+a+b x+b\right )}{a^2}\right \}\right \}\]
✓ Maple : cpu = 0.403 (sec), leaf count = 86
\[ \left \{ y \left ( x \right ) ={\frac {1}{2\,a} \left ( 3\,\tanh \left ( {\it RootOf} \left ( 729\,{x}^{3} \left ( \tanh \left ( {\it \_Z} \right ) \right ) ^{6}{a}^{6}-2187\,{x}^{3} \left ( \tanh \left ( {\it \_Z} \right ) \right ) ^{4}{a}^{6}+2187\,{x}^{3} \left ( \tanh \left ( {\it \_Z} \right ) \right ) ^{2}{a}^{6}-729\,{a}^{6}{x}^{3}+64\, \left ( {{\rm e}^{{\it \_Z}}} \right ) ^{2}{\it \_C1} \right ) \right ) a\sqrt {x}-a\sqrt {x}+2\,a+ \left ( 2+2\,x \right ) b \right ) } \right \} \]