Download 2. A - Brookwood High School

Matrices
Review Game!
I will stop looking back with regrets or looking
forward with fear and give the best I have today."
~Anonymous
1. What are the dimensions of
2. Give theCentry
in c22 and a23
and B?
6.
5.3.(1/2)C
2A
A +- B
4. -2C
151
51 18 


0
4 2x3

4
2
03 10
52
 16
2
1
9
 8 36
 12

 1
313x3
205 15
3
6


2 
Find x and y.
1.
2.
x=7
-8
y=3
4
10
1. BA
2. BC 4 2
5 
 8
 16

4


 16 4 
3. CD
4. AC Can’t be
done
Give
Givethe
theidentity
identitymatrix
matrixfor
foraa4x4.
2x2.
1 0
0  11
I  
I
0 00

0 0
0
0
0

11
0
0
0 
0

1
1. det(A)= -1 4 3.
2 det(C)= -40
Evaluate.

 1 36 34. C0
-1=
-1
2. A =  2 5 
 1
4  1 
5
10   0.5
0.8
0.1 
 2
 1
1
1    0.25 0.25 0.25 

4
4  
 4
1
13
1   0.25 0.65 0.05 
 4
20
20 
1. Write the matrix equation
2. Solve the system
 1 1  x  8 
2 1  y    1

   
(-7, 15)
1. Write the matrix equation
2. Solve the system
 1 1 1  x   14 
 4 1 5   y    22

  

 2 2 3   z   35 
(4, 3, -7)
3x + 5y = –3
10y – 2z = 2
x = –z
1. Write the matrix equation
2. Solve the system
3 5 0   x   3
0 10 2  y    2 

   
 1 0 1   z   0 
(-2, 0.6, 2)

2, 3 , 2
5

Susan babysat for 8 hours and worked at Taco Bell
for 3 hours. She made $58. When she babysat for 2
hours and worked at Taco Bell for 5 hours, she made
$40. How much does Susan make per hour babysitting and working at Taco Bell?
1. Write a system of equations to model the
situation.
8x + 3y = 58
2x + 5y = 40
2. Solve the system using matrix equations.
$5 Babysitting
$6 Taco Bell
A nurse is mixing a 3% saline solution and an 8%
saline solution to get 2 liters of a 5% saline solution.
How many liters of each solution must be combined?
1. Write a system of equations to model the
situation.
0.03x + 0.08y = 0.1
x + y = 2
2. Solve the system using matrix equations.
1.2 L of 3% solution
0.8 L of 8% solution
When working with matrices,
don’t forget…
And a…
Row x Column