a
$A \cdot(A d j A)=|A| I$
$|A|=\left|\begin{array}{lll}{x} & {3} & {2} \\ {1} & {y} & {4} \\ {2} & {2} & {z}\end{array}\right| $
$ =x(y z-8)-3(z-8)+2(2-2 y) $
$=x y z-(8 x+4 y+3 z)+28 $
$=60-20+28=68 $
$\therefore \,\,\,\,\,A \cdot (Adj\,A) = 68I = \left[ {\begin{array}{*{20}{c}}
{68}&0&0\\
0&{68}&0\\
0&0&{68}
\end{array}} \right]$