$\"\"$

For adding and subtracting matrices, their dimension should be equal.

First write the dimension of the matrix.

The dimensions of matrix are $\"\"$ .

The operation is possible. $\"\"$

Multiply the matrix by 3.

$\"\"$

$\"\"$ (Multiply each element by 3)

$\"\"$ (Simplify) $\"\"$

Perform the operation

$\"\"$ $\"\"$

$\"\"$ (Subtract the each elements)

$\"\"$ (Product of two same signs is positive)

$\"\"$ (Simplify) $\"\"$

The value of is $\"\"$ .