Matrix Practice

Find the determinant of the matrix.

• -30

• 0

• 31

• 6

Find the determinant of the matrix.

• 14

• -14

• 3

• 20

It takes Sarah 2 hours to make small purses and 3 hours to make big purses. She has a maximum of 18 hours a week. Which inequality represents this situation?

• 2x + 3y ≤ 18
• x + y ≤ 6
• x + y ≤ 9
• 3x + 2y ≤ 18

Tags

CCSS.HSA.CED.A.2

CCSS.HSA.CED.A.3

What is the inverse of this matrix?

• _{(1/25)  (-4/25)
  (3/25)  (13/25)}

• _{(1/5)  (-4/5)
  (3/5)  (13/5)}
• _{(6/25)  (-2/25)
  (2/25)  (9/25)}
• _{(1/150)  (-4/150)
  (3/150)  (13/150)}

Verify whether or not A and B are inverses of each other.

• They are because AB = I and BA = I

• They are not because AB = I but BA ≠ I

• They are because AB = 0 and BA = 0

• They are not because AB ≠ BA

Verify whether or not A and B are inverses of each other.

• They are because AB = I and BA = I

• They are not because AB = I but BA ≠ I

• They are because AB = 0 and BA = 0

• They are not because AB ≠ BA

Is this matrix invertible?

3 10

2 15

• Yes because the determinant is 30

• Yes because the determinant is 18

• No because it is not a square matrix.

• No because the determinant is 0.

Is this matrix invertible?

14

48

• Yes because the determinant is 30

• No because it is not a square matrix.

• Yes because the determinant is 45

• No because the determinant is 0.

Ethan and Taylor work at brunch place called Snooze. Their manager does not allow them to work more than 30 hours a week combined. Ethan wants to work at least 12 hours a week. Taylor wants to work at least two times the amount of hours that Ethan works.

Let E = the number of hours that Ethan works and T = the number of hours that Taylor works.

Select ALL of the inequalities that represent these constraints below.

• E + T ≤ 30

• E ≥ 12

• 2T ≥ E

• 2E ≥ T

• E + T ≥ 30

Texas Instruments makes scientific and graphing calculators. Every week, TI produces at least 40 scientific and 35 graphing calculators. However, due to a limitation on the allocation of resources, they can produce no more than 82 scientific and 60 graphing calculators per week. To remain listed on retail websites, they must ship out at least 110 calculators per week.

Which of the following vertices are NOT part of the feasible region?

• (50, 60)

• (82, 60)

• (40, 60)

• (82, 35)

• (75, 35)