### Home > A2C > Chapter 11 > Lesson 11.3.1 > Problem11-136

11-136.

Multiply the appropriate rows into the columns and then add.

$\begin{bmatrix}20 & 19 & 4 \\ 23 & 7 & -2 \end{bmatrix}$

Is the number of columns in the first matrix equal to the number or rows in the second matrix?

Not possible.

Find 2A before adding C.

$\begin{bmatrix} 1 & 6\\0 & 11 \end{bmatrix}$

Find AC before adding A.

$\begin{bmatrix} -2 & 6 \\ 12 & 8 \end{bmatrix}$