\[
\text { Let } A=\left[\begin{array}{rr}
-5 & 6 \\
-5 & -9
\end{array}\right] \text { and } B=\left[\begin{array}{rr}
7 & -1 \\
-5 & 0
\end{array}\right]
\]
Find $-3 A+2 B$

Step 1 ：Given matrices A and B as follows: \[ A=\left[\begin{array}{rr} -5 & 6 \ -5 & -9 \end{array}\right] \] and \[ B=\left[\begin{array}{rr} 7 & -1 \ -5 & 0 \end{array}\right] \]

Step 2 ：We are asked to find the result of the matrix operation \(-3 A+2 B\).

Step 3 ：To solve this, we first need to multiply each matrix by its corresponding scalar. This gives us \(-3A\) and \(2B\) as follows: \[ -3A=\left[\begin{array}{rr} 15 & -18 \ 15 & 27 \end{array}\right] \] and \[ 2B=\left[\begin{array}{rr} 14 & -2 \ -10 & 0 \end{array}\right] \]

Step 4 ：We then add the two resulting matrices together to get the final result: \[ -3A+2B=\left[\begin{array}{rr} 29 & -20 \ 5 & 27 \end{array}\right] \]

Step 5 ：So, the final answer is \[ -3 A+2 B=\boxed{\left[\begin{array}{rr} 29 & -20 \ 5 & 27 \end{array}\right]} \]