Chapter 10 - 10.2 - Operations with Matrices - 10.2 Exercises - Page 724: 11

Part A: Since A and B are not the same dimensions, A + B is undefined. Part B: Since A and B are not the same dimensions, A - B is undefined. Part C: $\begin{bmatrix} 18 & 0 & 9\\ -3 & -12 & 0\\ \end{bmatrix}$ Part D: Since A and B are not the same dimensions, 3A - 2B is undefined.

The dimensions of A are (2 x 3). The dimensions of B are (2 x 2). Part A: Since A and B are not the same dimensions, A + B is undefined. Part B: Since A and B are not the same dimensions, A - B is undefined. Part C: $\begin{bmatrix} 3(6) & 3(0) & 3(3)\\ 3(-1) & 3(-4) & 3(0)\\ \end{bmatrix}$ = $\begin{bmatrix} 18 & 0 & 9\\ -3 & -12 & 0\\ \end{bmatrix}$ Part D: Since A and B are not the same dimensions, 3A - 2B is undefined.