Answer
$\begin{bmatrix}
50&-3\\
18&21
\end{bmatrix}$
Work Step by Step
Refer to sum $\#15$ and $\#16$ for determination of $AC$ and $BC$, respectively.
$\implies AC+BC = \begin{bmatrix}28&-9\\4&23\end{bmatrix}+\begin{bmatrix}22&6\\14&-2\end{bmatrix}$
We add two matrices by adding their respective individual elements.
$\therefore AC+BC = \begin{bmatrix}28+22&-9+6\\4+14&23-2\end{bmatrix}=\begin{bmatrix}50&-3\\18&21\end{bmatrix}$
