\[ \left \{4 x'(t)+11 x(t)+9 y'(t)+31 y(t)=e^t,3 x'(t)+8 x(t)+7 y'(t)+24 y(t)=e^{2 t}\right \} \] ✓ Mathematica : cpu = 0.107911 (sec), leaf count = 162
\[\left \{\left \{x(t)\to -e^t t \left (-\frac {4 t}{5}+\frac {1}{36} e^t (30 t+19)-\frac {11}{25}\right )-e^t (t-1) \left (\frac {4 t}{5}-\frac {1}{36} e^t (30 t+49)+\frac {31}{25}\right )-c_1 e^{-4 t} (t-1)-c_2 e^{-4 t} t,y(t)\to e^t (t+1) \left (-\frac {4 t}{5}+\frac {1}{36} e^t (30 t+19)-\frac {11}{25}\right )+e^t t \left (\frac {4 t}{5}-\frac {1}{36} e^t (30 t+49)+\frac {31}{25}\right )+c_1 e^{-4 t} t+c_2 e^{-4 t} (t+1)\right \}\right \}\] ✓ Maple : cpu = 0.092 (sec), leaf count = 65
\[ \left \{ \left \{ x \left ( t \right ) ={{\rm e}^{-4\,t}}{\it \_C2}+{{\rm e}^{-4\,t}}t{\it \_C1}+{\frac {31\,{{\rm e}^{t}}}{25}}-{\frac {49\,{{\rm e}^{2\,t}}}{36}},y \left ( t \right ) ={\frac {19\,{{\rm e}^{2\,t}}}{36}}-{{\rm e}^{-4\,t}}{\it \_C2}-{{\rm e}^{-4\,t}}t{\it \_C1}-{{\rm e}^{-4\,t}}{\it \_C1}-{\frac {11\,{{\rm e}^{t}}}{25}} \right \} \right \} \]