Matrices Add and Subtract

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

Subtract

• 3    -8
  0   -1

• 3   -4
  8  -13

• -3   8
  0    1

• 3   -8
  -8    1

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

• 8

• 9.01

• 6

• 1

Find A-B

• -3     1
  7     -1

• 1     0
  1     -4

• -4       0
  6     -1

• not possible because rows do not match columns

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

Subtract

• 3    -8
  0   -1

• 3   -4
  8  -13

• -3   8
  0    1

• 3   -8
  -8    1

• 
• 
• 
• 

Subtract

• -5
  -8
  3
  10

• -9
  8
  3
  2

• 5
  -8
  3
  10

• -5
  8
  3
  2

• A
• B
• C
• D

What do a, b, c and d equal in this matrix addition?

• a = -1, b = 10, c = 7, d = -11

• a = -1, b = 10, c = -11, d = 7

• a = 10, b = -1, c = 7 , d = -11 

• a = 10, b = -1, c = -11, d = 7