Matrices

What are the dimensions of this matrix?

• 4x3

• 3x4

• 3

• 4

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

How many rows are in a 7 x 3 matrix?

• 7
• 3
• 21
• 10

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

Perform the indicated operation

• 
• 
• 
• 
• not possible

Perform the following operation

• 
• 
• 
• 
• not possible

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

How would a scalar multiplication be carried out for a matrix?

• Add the Scalar to every element in the matrix
• Dot product the rows of one matrix with the columns of the other matrix
• Multiply every element with the scalar to create a new matrix
• subtract the elements in the first matrix from the elements of the second matrix