For subtracting matrices, their dimension should be equal.
\First write the dimension of the matrix.
\The first matrix is 
The matrix has 2 row and 3 columns, so dimensions of matrix are
.
The second matrix is 
The matrix has 2 row and 3 columns, so dimensions of matrix are
.
The dimensions of matrix are equal. The operation of subtraction is possible.
\Subtract the corresponding elements.
\
Note: Subtracting matrics 

(Product of two same signs is positive)
(Subtract:
)
(Add:
)
The solution is
.