Intro Matrix

What must be true in order to ADD or SUBTRACT two matrices?

• They must be square.

• The dimensions must be equal.

• The determinant can't equal 0.

• The column of the 1st must equal the row of the 2nd.

What are the dimensions of this matrix?

• 2 x 3

• 3 x 2

• 6 x 1

• 1 x 6

In Matrix R (pictured) what is the value of element R_3,2

• 8

• 9.01

• 6

• 1

What must be true in order to SUBTRACT two matrices?

• They must be square.

• The dimensions must be equal.

• The determinant can't equal 0.

• The column of the 1st must equal the row of the 2nd.

Dimensions?

• a

• b

• c

• d

Add

• 11    8
  -4     2

• 3     2
  -6    -6

• -3    2
  -4    -6

• 10    8
  -6    2

Find A+B

• 8     10
  8      1 

• 12     25
  7     1

• 10     30
  0     1

• can't add two together because the rows dont match columns

Find A-B

• -3     1
  7     -1

• 1     0
  1     -4

• -4       0
  6     -1

• not possible because rows do not match columns

Add

• 11    8
  -4     2

• 3     2
  -6    -6

• -3    2
  -4    -6

• 10    8
  -6    2

What is the name of each entry of a matrix?

• Row

• Element

• Dimension

• Numbers