\[ 6 a^2 y(x)+5 a y'(x)+y''(x)-6 y(x)^2=0 \] ✗ Mathematica : cpu = 1.24408 (sec), leaf count = 0 , could not solve
DSolve[6*a^2*y[x] - 6*y[x]^2 + 5*a*Derivative[1][y][x] + Derivative[2][y][x] == 0, y[x], x]
✓ Maple : cpu = 0.094 (sec), leaf count = 27
\[ \left \{ y \left ( x \right ) ={\it WeierstrassP} \left ( -{\frac {{{\rm e}^{-ax}}}{a}}+{\it \_C1},0,{\it \_C2} \right ) \left ( {{\rm e}^{-ax}} \right ) ^{2} \right \} \]