Task Sets: Add, subtract, and multiply matrices - Common Core Math - HS Number and Quantity

1.

Compute $\begin{bmatrix}1 & 3\\5 & 2\end{bmatrix} + \begin{bmatrix}-2 & 4\\1 & -3\end{bmatrix}$ . Which matrix is the result?

A.

$\begin{bmatrix}-1 & 7\\6 & -1\end{bmatrix}$

B.

$\begin{bmatrix}3 & -1\\4 & 5\end{bmatrix}$

C.

$\begin{bmatrix}-2 & 12\\5 & -6\end{bmatrix}$

D.

$\begin{bmatrix}1 & 3\\5 & 2\end{bmatrix}$

2.

Compute $\begin{bmatrix}4 & -1\\3 & 7\end{bmatrix} - \begin{bmatrix}2 & 3\\-1 & 4\end{bmatrix}$ . What is the $(2,1)$ entry of the result?

3.

Matrix $A$ is $3 \times 2$ and matrix $B$ is $2 \times 5$ . What are the dimensions of $AB$ ?

A.

$2 \times 2$

B.

$3 \times 5$

C.

$3 \times 2$

D.

$5 \times 3$

4.

Let $A = \begin{bmatrix}2 & 1\\3 & 4\end{bmatrix}$ and $B = \begin{bmatrix}1 & 0\\2 & -1\end{bmatrix}$ . Find the $(1,1)$ entry of $AB$ .

5.

Let $A = \begin{bmatrix}2 & 1\\3 & 4\end{bmatrix}$ and $B = \begin{bmatrix}1 & 0\\2 & -1\end{bmatrix}$ . Find the $(2,2)$ entry of $AB$ .

Exercises: Add, Subtract, and Multiply Matrices