Matrices Reveiw

What is the dimension (order) of the matrix shown?

• ( 2 x 3 )

• ( 3 x 2 )

• ( 3 x 3 )

• ( 2 x 2 )

What entry is located in Row 3, Column 2?

• 4

• 7

• 2

• 5

Perform the operation if possible.

• A

• B

• C

• D

How many columns are in a 5 x 4 matrix?

• 5

• 4

• 20

• 9

Which of the following products can NOT be made from these matrices ?

• AB

• BA

• BC

• BD

What must be true in order to ADD 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.

Matrices can be multiplied only...

• if the row of the first matrix is equal to the column of the second matrix.

• if the column of the first matrix is equal to the column of the second matrix.

• if the column of the first matrix is equal to the row of the second matrix.

• if the row of the first matrix is equal to the row of the second matrix.

Add

• 11    8
  -4     2

• 3     2
  -6    -6

• -3    2
  -4    -6

• 10    8
  -6    2

Multiply

• 20     15    -10
  30     -5         0

• -20      15     -10
  30     -5          0

• 1        8       3
  11     4        5

• 20     -15     10
  -30         5        0  

Find B-A

• -4     0
  6     -1

• 1     0
  1     -4

• 4       0
  -6     1

• not possible because rows do not match columns