Answer
$$
5
\begin{bmatrix}
5 \\ -2
\end{bmatrix}
-1
\begin{bmatrix}
1\\-7
\end{bmatrix}
+3
\begin{bmatrix}
-8\\3
\end{bmatrix}
-2
\begin{bmatrix}
4\\-5
\end{bmatrix}
=
\begin{bmatrix}
-8 \\ 16
\end{bmatrix}
$$
Work Step by Step
Each column of the matrix is multiplied by the corresponding entry in the vector. We then add them all together, and they equal the value on the right hand side. This process follows directly from the relationship between matrix-vector multiplication and vector equations.