If matrix A can be multiplied by matrix B, can matrix B be multiplied by matrix A?
It depends on orders of matrices.
Matrix multiplication of A and B is possible when the number columns of A equals to the number of rows of B.
Matrix multiplication of B and A is possible when the number columns of B equals to the number of rows of A.
Since multiplication depends on equality of columns and rows of first matrix and second matrix respectively , hence multiplication of B and A should not determined until and unless orders of matrices are defined.