\[
\boxed{
 \left\{ t{\frac {\rm d}{{\rm d}t}}x \left( t \right) +2\,x \left( t \right) =t,t{\frac {\rm d}{{\rm d}t}}y \left( t \right) - \left( t+2 \right) x \left( t \right) -ty \left( t \right) =-t \right\} }
\]