Intro to Matrices Practice

How many columns are in a 5 x 4 matrix?

• 5

• 4

• 20

• 9

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

In Matrix R (pictured) what is the value of element R_3,2

• 8

• 9.01

• 6

• 1

What is matrix addition?

• Multiplying the corresponding elements of two matrices together.

• Subtracting the corresponding elements of two matrices.

• Dividing the corresponding elements of two matrices.

• Adding the corresponding elements of two matrices together.

What is matrix multiplication?

• Multiplying the corresponding elements of two matrices together.

• Subtracting the corresponding elements of two matrices.

• Dividing the corresponding elements of two matrices.

• Multiplying the rows of the first matrix with the columns of the second matrix.

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

What is the value of the variable in the equation?

• 
• 
• 
• 

Find A-B

• -3     1
  7     -1

• 1     0
  1     -4

• -4       0
  6     -1

• not possible because rows do not match columns

Find the product.

• undefined

• -3   16
  17   12
  8   -10

• 3   12 
  -15  -8
  -1   -3

Find B-A

• -3     1
  7     -1

• 1     0
  1     -4

• 4       0
  -6     1

• not possible because rows do not match columns