Answer
$\left[\begin{array}{rrr}
-8 & 7 & -15\\
7 & 0 & 22
\end{array}\right]$
Work Step by Step
A is a 2 by 3 matrix. 3A is also 2 by 3.
B is a 2 by 3 matrix. 2B is also 2 by 3.
3A-2B is defined, and is a 2 by 3 matrix.
$3A-2B=3\cdot\left[\begin{array}{lll}
0 & 3 & -5\\
1 & 2 & 6
\end{array}\right]-2\cdot\left[\begin{array}{lll}
4 & 1 & 0\\
-2 & 3 & -2
\end{array}\right]$
$=\left[\begin{array}{lll}
3\cdot 0 & 3\cdot 3 & 3\cdot(-5)\\
3\cdot 1 & 3\cdot 2 & 3\cdot 6
\end{array}\right]-\left[\begin{array}{lll}
2\cdot 4 & 2\cdot 1 & 2\cdot 0\\
2\cdot(-2) & 2\cdot 3 & 2\cdot(-2)
\end{array}\right]$
=$\left[\begin{array}{lll}
0-8 & 9-2 & -15-0\\
3-(-4) & 6-6 & 18-(-4)
\end{array}\right]$
=$\left[\begin{array}{rrr}
-8 & 7 & -15\\
7 & 0 & 22
\end{array}\right]$
