A scalar and matrix multiplication problem

Answer:
[tex]\left[\begin{array}{ccc}-32\\4\\20\\-36\end{array}\right][/tex]
Step-by-step explanation:
The product of a scalar times the matrix involves the product of that scalar times each of the elements of the matrix, resulting on the multiplication by "-4" of each of the four elements as shown below. These new product values end up being the new matrix elements.
[tex]-4*\left[\begin{array}{ccc}8\\-1\\-5\\9\end{array}\right] = \left[\begin{array}{ccc}-32\\4\\20\\-36\end{array}\right][/tex]
Answer:
[-32 4 20 -36]
Step-by-step explanation:
You only need to multiply the single number by the matrix:
[tex]\left[\begin{array}{ccc}-32\\4\\20\\-36\end{array}\right][/tex]