Multiplication of two matrices possible if the number of columns in the

first matrix equals the number of rows in the second matrix.

The dimensions of the matrix R are  and the number of columns in

the matrix R is 2.

The dimensions of the matrix S are and the number of the rows in the matrix S is 2.

The number of columns in the matrix R equals the number of rows in the matrix S.

So, matrix product AB is possible. Its dimensions are.

The matrix product AB is defined and matrix AB dimensions are .