\[ \left \{t x'(t)+y(t)=0,x(t)+t y'(t)=0\right \} \] ✓ Mathematica : cpu = 0.0052503 (sec), leaf count = 31
\[\left \{\left \{x(t)\to c_1 t+\frac {c_2}{t},y(t)\to \frac {c_2}{t}-c_1 t\right \}\right \}\]
✓ Maple : cpu = 0.036 (sec), leaf count = 31
\[ \left \{ \left \{ x \left ( t \right ) ={\frac {{\it \_C2}\,{t}^{2}+{\it \_C1}}{t}},y \left ( t \right ) ={\frac {-{\it \_C2}\,{t}^{2}+{\it \_C1}}{t}} \right \} \right \} \]