Answer
$\begin{bmatrix}-11&-19\\-3&5\\6&-22\end{bmatrix}$
Work Step by Step
We are given the matrices:
$A=\begin{bmatrix}1&-1\\0&-4\\3&2\end{bmatrix},C=\begin{bmatrix}4&6\\1&-3\\-1&8\end{bmatrix}$
Compute $A-3C$:
$A-3C=\begin{bmatrix}1&-1\\0&-4\\3&2\end{bmatrix}-3\begin{bmatrix}4&6\\1&-3\\-1&8\end{bmatrix}$
$=\begin{bmatrix}1&-1\\0&-4\\3&2\end{bmatrix}-\begin{bmatrix}12&18\\3&-9\\-3&24\end{bmatrix}$
$=\begin{bmatrix}1-12&-1-18\\0-3&-4-(-9)\\3-(-3)&2-24\end{bmatrix}$
$=\begin{bmatrix}-11&-19\\-3&5\\6&-22\end{bmatrix}$
