Matrix Addition and Subtraction Lesson

Adding and Subtracting Matrices

Multiple Select

What are words whose meaning is similar to that of corresponding (in the same place in two similar situations) There are more than one answer.

• different

• matching

• equivalent

• related

• similar

Matrix - matrices (plural)

A matrix is a rectangular array of numbers written within brackets. A matrix with m horizontal rows

and n vertical columns is an m x n matrix .

Rows x Columns Matrix

To add or subtract matrices A and B, add or subtract the corresponding elements.

Corresponding elements are elements in the same position in each matrix. 

Multiple Choice

How many rows are in a 7 x 3 matrix?

• 7

• 3

• 21

• 10

Multiple Choice

Find A+B

• 8 10

  8 1

• 12 25

  7 1

• 10 30

  0 1

• can't answer two together because the rows don't match columns.

Multiple Choice

What must be true in order to ADD two matrices?

• The dimensions must be equal.

• They must be square.

• The determinant can't equal 0.

Multiple Choice

Subtract

• -9

  8

  3

  2

• -5

  8

  3

  2

Multiple Choice

What are the dimensions of this matrix?

• 2 x 3

• 3 x 2

• 6 x 1

• 1 x 6

Multiple Choice

How many columns are in a 5 x 4 matrix?

• 5

• 4

• 20

• 9

How to be sure that two matrices are equal.

- Numbers of rows
- Number of columns
- Corresponding Elements

Multiple Choice

Can the operation be performed?

• Yes

• No

• Sometimes

• only Ms. Brandee knows

Multiple Choice

Given these matrices find D - A

• None

Find the values of w, x, y and z

First identify the corresponding elements. Then solve for the variable.

Poll

On a scale of 1-5 (5 being very confident and 1 being not confident) how confident are you to identify the dimensions of matrix.

• 1

• 2

• 3

• 4

• 5

Poll

On a scale of 1-5 (5 being very confident and 1 being not confident) how confident are you to add and subtract matrices.

• 1

• 2

• 3

• 4

• 5

Poll

On a scale of 1-5 (5 being very confident and 1 being not confident) how confident are you to find variables on a matrix.

• 1

• 2

• 3

• 4

• 5