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

vec$(x{)}^{\text{'}}=\left[\begin{array}{ccc}-3& -16& -3\end{array}\right]$

$1$vec$(x)$

$,\left[\begin{array}{c}{x}_1(t)\end{array}\right]$

$x_2(t)=c_1\left[\begin{array}{c}\end{array}\right]$

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