## Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

$\begin{bmatrix} -8 & 7 & -15\\ 7 & 0 & 22 \end{bmatrix}$
Since, matrices $A$ and $B$ are both $2 \times 3$ matrices and have the same dimensions, we know that their subtraction, $3A-2B$, is defined. $3A-2B=3 \begin{bmatrix} 0 & 3 & -5\\ 1 & 2 & 6 \end{bmatrix}-2\begin{bmatrix} 4 & 1 & 0\\ -2 & 3 & -2 \end{bmatrix} \\=\begin{bmatrix} 3\cdot 0 & 3\cdot 3 & 3\cdot(-5)\\ 3\cdot 1 & 3\cdot 2 & 3\cdot 6 \end{bmatrix}-\begin{bmatrix} 2\cdot 4 & 2\cdot 1 & 2\cdot 0\\ 2\cdot(-2) & 2\cdot 3 & 2\cdot(-2) \end{bmatrix} \\=\begin{bmatrix} 0-8 & 9-2 & -15-0\\ 3-(-4) & 6-6 & 18-(-4) \end{bmatrix}\\=\begin{bmatrix} -8 & 7 & -15\\ 7 & 0 & 22 \end{bmatrix}$