$\"\"$

For subtracting matrices, their dimension should be equal.

First write the dimension of the matrix.

The dimension of matrix B are $\"\"$ .

The dimension of matrix D are $\"\"$ . $\"\"$

The operation $\"\"$ 5B $\"\"$ 2D is not possible,

since the dimensions are not equal. $\"\"$

The operation of $\"\"$ 5B $\"\"$ 2D is impossible.