Multiplying matrices by scalars is relatively simple. Just multiply each element by the scalar. Take for instance scalar $k$ and matrix $\mathbf{A}$ with elements $a_{ij}$:
$k\mathbf{A}=ka_{ij}$
>[!example]-
$3\begin{bmatrix}1&0\\2&3\end{bmatrix}=\begin{bmatrix}3&0\\6&9\end{bmatrix}$