Algebra 2 Review Matrices

Add

• 11    8
  -4     2
• 3     2
  -6    -6
• -3    2
  -4    -6
• 10    8
  -6    2

Find A-B

• -3     1
  7     -1
• 1     0
  1     -4
• -4       0
  6     -1
• not possible because rows do not match columns

What are the dimensions of this matrix?

• 2 x 3
• 3 x 2
• 6 x 1
• 1 x 6

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  

In Matrix R (pictured) what element is in the second row, third column?

• 8
• 9.01
• 6
• 1

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.

How many rows are in a 7 x 3 matrix?

• 7
• 3
• 21
• 10

How many columns are in a 5 x 4 matrix?

• 5
• 4
• 20
• 9

Subtract

• 3    -8
  0   -1
• 3   -4
  8  -13
• -3   8
  0    1
• 3   -8
  -8    1

Perform the matrix multiplication, if possible.

• 
• 
• 
• Cannot be multiplied, dimensions not compatible.