Question

Can someone find the value of: 3A-B-2C

Answer 1

`~~~~~~3A - B - 2C\\\\=3\begin{bmatrix} 1&0&3\\-2&5&-1 \end{bmatrix}-\begin{bmatrix} 1&0&3\\2&1&0 \end{bmatrix}-2\begin{bmatrix} x&2&y\\-1&5&-1 \end{bmatrix}\\\\\\=\begin{bmatrix} 3&0&9\\-6&15&-3 \end{bmatrix}-\begin{bmatrix} 1&0&3\\2&1&0 \end{bmatrix}-\begin{bmatrix} 2x&4&2y\\-2&10&-2 \end{bmatrix}\\\\\\=\begin{bmatrix} 3-1&0-0&9-3\\-6-2&15-1&-3-0 \end{bmatrix}-\begin{bmatrix} 2x&4&2y\\-2&10&-2 \end{bmatrix}\\\\\\`

`=\begin{bmatrix} 2&0&6\\-8&14&-3 \end{bmatrix}-\begin{bmatrix} 2x&4&2y\\-2&10&-2 \end{bmatrix}\\\\\\=\begin{bmatrix} 2-2x&0-4&6-2y\\-8+2&14-10&-3+2 \end{bmatrix}\\\\\\=\begin{bmatrix} 2-2x&-4&6-2y\\-6&4&-1 \end{bmatrix}`