Find the most general real$-$valued solution to the linear system of differential equations

$\left[\begin{array}{c}{x}^{\text{'}}\end{array}\right]$

$y^{\text{'}}=\left[\begin{array}{ccc}3& -36& 3\end{array}\right]$

$1\left[\begin{array}{c}x\end{array}\right]$

$y$

$y(t)$