Respuesta :

Answer:

Step-by-step explanation:

Focus on #7.  Let's combine the first two matrices inside round parentheses.

We get  

  -2 - 1

   4 + 3

and so the original problems becomes

     -3         4

3( [     ] + [      ] )

      7          2

Combining the two matrices, we get the following:

     1            3

3([      ]) = [      ]

     9            9