[tex]\left[\begin{array}{ccc}3 & 9 \\\\ 5& -2\end{array}\right]+\left[\begin{array}{ccc}6 & 0\\\\ \!\!-8 & 4\end{array}\right]=\left[\begin{array}{ccc} 3+6 & 9+0 \\\\5-8 &-2+4 \end{array}\right] =\left[\begin{array}{ccc} 9& 9 \\\\ -3 & 2\end{array}\right][/tex]
