How do I set these up?
Use matrices A,B,C and D to find each scalar product and sum, or difference if possible. If an operation is not defined, label it not defined.
A = [6 1 0 8] B=[1 3]
[-4 3 7 11] [-2 4]

C= [-2 1] D=[5 -2]
[4 0] [3 6]
[2 2]
[1 1]

11.3A
A = 3[6 1 0 8]
[-4 3 7 11]

13.AB
A=[6 1 0 8] B= [1 3]
[-4 3 7 11] [-2 4]

15.AC-BD

Question

How do I set these up?
Use matrices A,B,C and D to find each scalar product and sum, or difference if possible. If an operation is not defined, label it not defined. 
A = [6   1   0  8]                        B=[1    3]
       [-4  3   7   11]                          [-2   4]

C= [-2  1]                               D=[5   -2]
      [4   0]                                    [3    6]
      [2   2]
      [1   1]

11.3A
A = 3[6   1    0   8]         
        [-4  3   7   11]

13.AB
A=[6   1    0   8]       B= [1  3]     
     [-4  3   7   11]            [-2  4]

15.AC-BD