2 X 2 Matrices

What do w, x, y and z equal in this matrix subtraction?

• w = 13, x = 4, y = 7, z = 23

• w = 13, x = -4, y = 11, z = 23

• w = 13, x = 4, y = 11, z = 23

• w = 13, x = 4, y = 11, z = 17

What do m, n, p and q equal in this scalar matrix multiplication?

• m=8, n=9, p=-4, q=4 

• m=15, n = -45, p=20, q=-5

• m=20, n=-5, p=15, q=-45

• m=-5, n=20, p=-45, q=15

find: B*A

• 47     30
  9     5

• 17     15
  42     35

• 10     25
  7     1

• not possible because rows do not match columns

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.

• 17   12
  25   18
• 8   9
  12   6
• 6   6
  7   5
• 12   10
  10   12

Multiply

• 
• 
• 
• 

Find the product of the two matrices.

• 17   12
  25   18

• 8   9
  12   6

• 6   6
  7   5

• 12   10
  10   12

Find the product of the two matrices.

• 1   2
  6   -8

• -3   -5
  -5   -11

• -2     8
  -6   -12

• 2  -3
  5   -2

• A
• B
• C
• D

find: B*A

• 47     30
  9     5

• 17     15
  42     35

• 10     25
  7     1

• not possible because rows do not match columns