If $ A = \begin{bmatrix} 3 & -2 \\ 4 & -2 \end{bmatrix} $ and $ I = \begin{bmatrix} 1 & 0 \\ 0 & 1 \end{bmatrix} $ find $k$ so that $A^2 = kA - 2I$

Question

$\begin{array}{1 1} k=1\\ k=2 \\ k=-1 \\ k=0 \end{array} $