Solve the system
\begin{array}{ll}x^{\prime}=x+y, & x(0)=1 \\y^{\prime}=-3 x-y, & y(0)=0\end{array}\quad\quad\quad\quad\quad (10)Solve the system
\begin{array}{ll}x^{\prime}=x+y, & x(0)=1 \\y^{\prime}=-3 x-y, & y(0)=0\end{array}\quad\quad\quad\quad\quad (10)