Answer:
[tex]-5B = \begin{bmatrix}-15&10\\ 20&40\end{bmatrix}[/tex]
Step-by-step explanation:
[tex]B=\begin{bmatrix}3&-2\\ -4&-8\end{bmatrix}[/tex]
[tex]\Longrightarrow -5B = -5 \times\begin{bmatrix}3&-2\\ -4&-8\end{bmatrix}[/tex]
[tex]\Longrightarrow -5B = \begin{bmatrix}-5 \times3&-5 \times-2\\ -5 \times-4&-5 \times-8\end{bmatrix}[/tex]
[tex]\Longrightarrow -5B = \begin{bmatrix}-15&10\\ 20&40\end{bmatrix}[/tex]
