Answer:
Step-by-step explanation:
The sum of two matrices is the sum of corresponding terms.
[tex]\left[\begin{array}{ccc}3&1&0\\-1&2&4\\9&7&-2\end{array}\right] +\left[\begin{array}{ccc}5&2&4\\1&12&3\\11&3&-2\end{array}\right] =\left[\begin{array}{ccc}8&3&4\\0&14&7\\20&10&-4\end{array}\right][/tex]