Solve the linear system below by substitution. $$\left\lbrace \begin{array}{rcr} x-3y-z & = & -3 \\ x+2y+z & = & 3 \\ -3y-z & = & 5 \end{array} \right.$$ Note: your answers must be fractions (decimals are not allowed).

$x =$
$y =$
$z =$