Question 1

Write the augmented matrix for the system. Do not solve the system.
-$$\begin{aligned}
7 x - 2 z & = - 9 \
2 y + 7 z & = 9 \
7 x + 9 y + 4 z & = 6
\end{aligned}$$

Accepted Answer

A) 
$\left[ \begin{array} { r r r } 7 & 0 & - 2 \ 0 & 2 & 7 \ 7 & 9 & 4 \end{array} \right]$ 
B) 
$\left[ \begin{array} { r r r | r } 7 & 0 & 7 & - 9 \ 0 & 2 & 9 & 9 \ - 2 & 7 & 4 & 6 \end{array} \right]$ 
C) 
$\left[ \begin{array} { r r r | r } 7 & 0 & - 2 & - 9 \ 0 & 2 & 7 & 9 \ 7 & 9 & 4 & 6 \end{array} \right]$ 
D)

$\left[ \begin{array} { r r r | r } 7 & - 2 & 0 & - 9 \ 2 & 7 & 0 & 9 \ 7 & 9 & 4 & 6 \end{array} \right]$ 
A) 
$\left[ \begin{array} { r r r } 7 & 0 & - 2 \ 0 & 2 & 7 \ 7 & 9 & 4 \end{array} \right]$ 
B) 
$\left[ \begin{array} { r r r | r } 7 & 0 & 7 & - 9 \ 0 & 2 & 9 & 9 \ - 2 & 7 & 4 & 6 \end{array} \right]$ 
C) 
$\left[ \begin{array} { r r r | r } 7 & 0 & - 2 & - 9 \ 0 & 2 & 7 & 9 \ 7 & 9 & 4 & 6 \end{array} \right]$ 
D)

$\left[ \begin{array} { r r r | r } 7 & - 2 & 0 & - 9 \ 2 & 7 & 0 & 9 \ 7 & 9 & 4 & 6 \end{array} \right]$

Question 2

Solve the system.
-$$\begin{array} { l } 
\frac { 2 } { x } + \frac { 5 } { y } + \frac { 1 } { z } = - \frac { 3 } { 8 } \
\frac { 8 } { x } + \frac { 1 } { y } - \frac { 2 } { z } = 4 \
\frac { 1 } { x } + \frac { 1 } { y } - \frac { 3 } { z } = \frac { 5 } { 8 }
\end{array}$$

Accepted Answer

A)  $\{ ( 2 , - 4,8 ) \}$ 
B)  $\{ ( 2 , - 4 , - 8 ) \}$ 
C)  $\left\{ \left( \frac { 1 } { 2 } , - \frac { 1 } { 4 } , \frac { 1 } { 8 } \right) \right\}$ 
D)  $\left\{ \left( \frac { 1 } { 2 } , - \frac { 1 } { 4 } , - \frac { 1 } { 8 } \right) \right\}$ 
A)  $\{ ( 2 , - 4,8 ) \}$ 
B)  $\{ ( 2 , - 4 , - 8 ) \}$ 
C)  $\left\{ \left( \frac { 1 } { 2 } , - \frac { 1 } { 4 } , \frac { 1 } { 8 } \right) \right\}$ 
D)  $\left\{ \left( \frac { 1 } { 2 } , - \frac { 1 } { 4 } , - \frac { 1 } { 8 } \right) \right\}$

Question 3

Graph the inequality.
-$y \geq-2$

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
A) 
  
B) 
  
C) 
  
D)

Question 4

Find the value of the determinant.
-$$\left| \begin{array} { r r r } 
5 & 5 & - 4 \
- 4 & - 3 & - 3 \
3 & - 2 & 0
\end{array} \right|$$

Accepted Answer

A)  143 
B)  $- 53$ 
C)  $- 143$ 
D)  $- 11$ 
A)  143 
B)  $- 53$ 
C)  $- 143$ 
D)  $- 11$

Question 5

Find the values of the variables for which the statement is true, if possible.
-$\left[ \begin{array} { l l l } - 8 & b & - 4 \end{array} \right] + \left[ \begin{array} { l l l } a & 9 & c \end{array} \right] = \left[ \begin{array} { l l l } 6 & 6 & - 5 \end{array} \right]$

Accepted Answer

A)  $\mathrm { a } = 14 ; \mathrm { b } = - 3 ; \mathrm { c } = - 1$ 
B)  $\mathrm { a } = - 2 ; \mathrm { b } = 15 ; \mathrm { c } = - 9$ 
C)  $a = - 14 ; b = 3 ; c = 1$ 
D)  $\mathrm { a } = - \frac { 3 } { 4 } ; \mathrm { b } = \frac { 2 } { 3 } ; \mathrm { c } = \frac { 5 } { 4 }$ 
A)  $\mathrm { a } = 14 ; \mathrm { b } = - 3 ; \mathrm { c } = - 1$ 
B)  $\mathrm { a } = - 2 ; \mathrm { b } = 15 ; \mathrm { c } = - 9$ 
C)  $a = - 14 ; b = 3 ; c = 1$ 
D)  $\mathrm { a } = - \frac { 3 } { 4 } ; \mathrm { b } = \frac { 2 } { 3 } ; \mathrm { c } = \frac { 5 } { 4 }$

Question 6

Use a graphing calculator to solve the nonlinear system. Give x- and y-coordinates to the nearest hundredth.
-$$\begin{array} { l } 
x ^ { 2 } - y ^ { 2 } = 7.82 \
x = 2 y - 5
\end{array}$$

Accepted Answer

A)  $\{ ( - 2.97,1.01 ) , ( 6.31,5.65 ) \}$ 
B)  $\{ ( - 2.97 , - 1.01 ) , ( 6.31 , - 5.65 ) \}$ 
C)  $\{ ( - 6.31,5.65 ) , ( 2.97,1.01 ) \}$ 
D)  $\{ ( - 6.31 , - 5.65 ) , ( 2.97 , - 1.01 ) \}$ 
A)  $\{ ( - 2.97,1.01 ) , ( 6.31,5.65 ) \}$ 
B)  $\{ ( - 2.97 , - 1.01 ) , ( 6.31 , - 5.65 ) \}$ 
C)  $\{ ( - 6.31,5.65 ) , ( 2.97,1.01 ) \}$ 
D)  $\{ ( - 6.31 , - 5.65 ) , ( 2.97 , - 1.01 ) \}$

Question 7

Find the inverse, if it exists, for the matrix.
-$$\left[ \begin{array} { l l l } 
5 & - 2 & 4 \
10 & - 3 & 8 \
5 & - 1 & 4
\end{array} \right]$$

Accepted Answer

A) 
$$\left[ \begin{array} { l l l } 
\frac { 2 } { 5 } & \frac { 1 } { 5 } & - \frac { 1 } { 2 } \
\frac { 1 } { 2 } & \frac { 4 } { 3 } & \frac { 5 } { 8 } \
1 & - 4 & \frac { 1 } { 4 }
\end{array} \right]$$ 
B)  The inverse does not exist. 
C) 
$$\left[ \begin{array} { l l l } 
\frac { 1 } { 5 } & \frac { 1 } { 10 } & \frac { 1 } { 4 } \
\frac { 1 } { 10 } & - \frac { 1 } { 3 } & \frac { 1 } { 8 } \
\frac { 1 } { 5 } & - 1 & \frac { 1 } { 4 }
\end{array} \right]$$ 
D) 
$\left[\begin{array}{ccc}
5 & 10 & 5 \
-2 & -3 & -1 \
4 & 8 & 4
\end{array}\right]$ 
A) 
$$\left[ \begin{array} { l l l } 
\frac { 2 } { 5 } & \frac { 1 } { 5 } & - \frac { 1 } { 2 } \
\frac { 1 } { 2 } & \frac { 4 } { 3 } & \frac { 5 } { 8 } \
1 & - 4 & \frac { 1 } { 4 }
\end{array} \right]$$ 
B)  The inverse does not exist. 
C) 
$$\left[ \begin{array} { l l l } 
\frac { 1 } { 5 } & \frac { 1 } { 10 } & \frac { 1 } { 4 } \
\frac { 1 } { 10 } & - \frac { 1 } { 3 } & \frac { 1 } { 8 } \
\frac { 1 } { 5 } & - 1 & \frac { 1 } { 4 }
\end{array} \right]$$ 
D) 
$\left[\begin{array}{ccc}
5 & 10 & 5 \
-2 & -3 & -1 \
4 & 8 & 4
\end{array}\right]$

Question 8

Solve the system by substitution.
-$$\begin{aligned}
3 x + 7 y & = 2 \
9 y & = 30 + 2 x
\end{aligned}$$

Accepted Answer

A)  $\left. \left\{ - \frac { 192 } { 41 } , \frac { 94 } { 41 } \right) \right\}$ 
B)  $\left\{ \left( - \frac { 192 } { 41 } , - \frac { 360 } { 41 } \right) \right\}$ 
C)  $\left\{ \left( - \frac { 192 } { 41 } , - \frac { 40 } { 41 } \right) \right\}$ 
D)  $\left\{ \left( \frac { 94 } { 41 } , - \frac { 192 } { 41 } \right) \right\}$ 
A)  $\left. \left\{ - \frac { 192 } { 41 } , \frac { 94 } { 41 } \right) \right\}$ 
B)  $\left\{ \left( - \frac { 192 } { 41 } , - \frac { 360 } { 41 } \right) \right\}$ 
C)  $\left\{ \left( - \frac { 192 } { 41 } , - \frac { 40 } { 41 } \right) \right\}$ 
D)  $\left\{ \left( \frac { 94 } { 41 } , - \frac { 192 } { 41 } \right) \right\}$

Question 9

Graph the solution set of the system of inequalities.
-

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
A) 
  
B) 
  
C) 
  
D)

Question 10

Perform the operation or operations when possible.
-$\left[ \begin{array} { l l } 1 & 4 \end{array} \right] + \left[ \begin{array} { r } - 1 \ 9 \end{array} \right]$

Accepted Answer

A)  They cannot be added. 
B) 
$$\left[ \begin{array} { r r } 
1 & - 1 \
4 & 9
\end{array} \right]$$ 
C) 
$\left[ \begin{array} { l l } 0 & 13 \end{array} \right]$ 
D) 
$\left[\begin{array}{r}
0 \
13
\end{array}\right]$ 
A)  They cannot be added. 
B) 
$$\left[ \begin{array} { r r } 
1 & - 1 \
4 & 9
\end{array} \right]$$ 
C) 
$\left[ \begin{array} { l l } 0 & 13 \end{array} \right]$ 
D) 
$\left[\begin{array}{r}
0 \
13
\end{array}\right]$

Question 11

Graph the solution set of the system of inequalities.
-

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
A) 
  
B) 
  
C) 
  
D)

Question 12

Give all solutions of the nonlinear system of equations, including those with nonreal complex components.
-$$\begin{array} { l } 
x ^ { 2 } + x y + y ^ { 2 } = 19 \
x + y = 2
\end{array}$$

Accepted Answer

A)  $\{ ( - 3,5 ) \}$ 
B)  $\{ ( 5 , - 3 ) \}$ 
C)  $\{ ( 5 , - 3 ) , ( - 3,5 ) \}$ 
D)  $\{ ( 4 , - 2 ) , ( - 4,6 ) \}$ 
A)  $\{ ( - 3,5 ) \}$ 
B)  $\{ ( 5 , - 3 ) \}$ 
C)  $\{ ( 5 , - 3 ) , ( - 3,5 ) \}$ 
D)  $\{ ( 4 , - 2 ) , ( - 4,6 ) \}$

Question 13

Graph the inequality.
-$x-y<-2$

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
A) 
  
B) 
  
C) 
  
D)

Question 14

Graph the solution set of the system of inequalities.
-

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
A) 
  
B) 
  
C) 
  
D)

Question 15

Find the matrix product when possible.
-$$\left[ \begin{array} { r r r } 
- 5 & 7 & 9 \
- 1 & - 8 & 4
\end{array} \right] \left[ \begin{array} { l } 
- 2 \
- 8 \
- 2
\end{array} \right]$$

Accepted Answer

A) 
$\left[ \begin{array} { r r r } - 5 & 7 & 9 \ - 1 & - 8 & 4 \ - 2 & - 8 & - 2 \end{array} \right]$ 
B) 
[-64 58] 
C) 
$\left[ \begin{array} { r } - 64 \ 58 \end{array} \right]$ 
D) 
$\left[ \begin{array} { r } 58 \ - 64 \end{array} \right]$ 
A) 
$\left[ \begin{array} { r r r } - 5 & 7 & 9 \ - 1 & - 8 & 4 \ - 2 & - 8 & - 2 \end{array} \right]$ 
B) 
[-64 58] 
C) 
$\left[ \begin{array} { r } - 64 \ 58 \end{array} \right]$ 
D) 
$\left[ \begin{array} { r } 58 \ - 64 \end{array} \right]$

Question 16

Perform the operation or operations when possible.
-$$\left[ \begin{array} { r r } 
- 3 & 1 \
2 & 5
\end{array} \right] + \left[ \begin{array} { l l } 
6 & 2 \
3 & 3
\end{array} \right]$$

Accepted Answer

A) 
$\left[ \begin{array} { r r } 3 & - 1 \ 0 & 0 \end{array} \right]$ 
B) 
$\left[ \begin{array} { l l } 3 & 4 \ 4 & 8 \end{array} \right]$ 
C) 
$\left[ \begin{array} { l l } 3 & 3 \ 5 & 8 \end{array} \right]$ 
D) 
[19] 
A) 
$\left[ \begin{array} { r r } 3 & - 1 \ 0 & 0 \end{array} \right]$ 
B) 
$\left[ \begin{array} { l l } 3 & 4 \ 4 & 8 \end{array} \right]$ 
C) 
$\left[ \begin{array} { l l } 3 & 3 \ 5 & 8 \end{array} \right]$ 
D) 
[19]

Question 17

Solve the problem.
-A bookstore is having a sale. All books included in the sale have a colored sticker on them to indicate the sale price. There are green stickers, red stickers, and orange stickers. Bob, Sue, and Fred each make purchases of books that are on sale. Each row of the table gives information about the numbers of book purchases and the total cost of the purchase (before taxes).

Use this information to set up a matrix equation of the form $A X = B$, which can be solved to determine the price for each type of sale book. Solve this matrix equation to find the price of a book with a green sticker.
Use the fact that for $A = \left[ \begin{array} { l l l } 1 & 2 & 2 \ 1 & 3 & 2 \ 1 & 2 & 3 \end{array} \right] , A ^ { - 1 } = \left[ \begin{array} { r r r } 5 & - 2 & - 2 \ - 1 & 1 & 0 \ - 1 & 0 & 1 \end{array} \right]$.

Accepted Answer

A)  $\$ 4.89$ 
B)  $\$ 4.99$ 
C)  $\$ 4.91$ 
D)  $\$ 4.96$ 
A)  $\$ 4.89$ 
B)  $\$ 4.99$ 
C)  $\$ 4.91$ 
D)  $\$ 4.96$

Question 18

Solve the problem using matrices.
-Ron attends a cocktail party (with his graphing calculator in his pocket). He wants to limit his food intake to 160 g protein, 142 g fat, and 186 g carbohydrate. According to the health-conscious
Hostess, the marinated mushroom caps have 3 g protein, 5 g fat, and 9 g carbohydrate; the spicy
Meatballs have 14 g protein, 7 g fat, and 15 g carbohydrate; and the deviled eggs have 13 g protein,
15 g fat, and 6 g carbohydrate. How many of each snack can he eat to obtain his goal?

Accepted Answer

A)  4 mushrooms; 8 meatballs; 6 eggs 
B)  8 mushrooms; 6 meatballs; 4 eggs 
C)  6 mushrooms; 4 meatballs; 8 eggs 
D)  9 mushrooms; 7 meatballs; 5 eggs 
A)  4 mushrooms; 8 meatballs; 6 eggs 
B)  8 mushrooms; 6 meatballs; 4 eggs 
C)  6 mushrooms; 4 meatballs; 8 eggs 
D)  9 mushrooms; 7 meatballs; 5 eggs

Question 19

Solve the linear programming problem.
-The Acme Class Ring Company designs and sells two types of rings: the VIP and the SST. They can produce up to 24 rings each day using up to 60 total man -hours of labor. It takes 3 man-hours to make one VIP ring and 2 man-hours to make one SST ring. How many of each type of ring should be made daily to maximize the company's profit, if the profit on a VIP ring is $\$ 40$ and on an SST ring is $\$ 35$ ?

Accepted Answer

A)  16 VIP and 8 SST 
B)  14 VIP and 10 SST 
C)  12 VIP and 12 SST 
D)  $18 \mathrm { VIP }$ and $6 \mathrm { SST }$ 
A)  16 VIP and 8 SST 
B)  14 VIP and 10 SST 
C)  12 VIP and 12 SST 
D)  $18 \mathrm { VIP }$ and $6 \mathrm { SST }$

Question 20

Use a graphing calculator to find the inverse of the matrix. Give five decimal places, if necessary.
-$$A = \left[ \begin{array} { c c c } 
1.52 & 5.55 & 4 \
- 0.63 & 7.33 & 3.21 \
8.2 & 0.003 & - 2.8
\end{array} \right]$$

Accepted Answer

A) 
$\left[ \begin{array} { l l l } 0 & 0 & 1 \ 0 & 1 & 0 \ 1 & 0 & 0 \end{array} \right]$ 
B) 
$$\left[ \begin{array} { r c r } 
0.02137 & - 0.01623 & 0.01192 \
- 0.27464 & 0.34436 & 0.00245 \
0.62294 & - 0.47163 & - 0.00792
\end{array} \right]$$ 
C) 
 $\left[ \begin{array} { r c c } 0.65789 & 0.18018 & 0.25 \ - 1.58730 & 0.13643 & 0.31153 \ 0.12195 & 333.33333 & - 0.35714 \end{array} \right]$ 
D) 
$$\left[ \begin{array} { r r c } 
0.15171 & - 0.11491 & 0.08500 \
- 0.18145 & 0.27379 & 0.05467 \
0.44411 & - 0.33622 & - 0.10815
\end{array} \right]$$ 
A) 
$\left[ \begin{array} { l l l } 0 & 0 & 1 \ 0 & 1 & 0 \ 1 & 0 & 0 \end{array} \right]$ 
B) 
$$\left[ \begin{array} { r c r } 
0.02137 & - 0.01623 & 0.01192 \
- 0.27464 & 0.34436 & 0.00245 \
0.62294 & - 0.47163 & - 0.00792
\end{array} \right]$$ 
C) 
 $\left[ \begin{array} { r c c } 0.65789 & 0.18018 & 0.25 \ - 1.58730 & 0.13643 & 0.31153 \ 0.12195 & 333.33333 & - 0.35714 \end{array} \right]$ 
D) 
$$\left[ \begin{array} { r r c } 
0.15171 & - 0.11491 & 0.08500 \
- 0.18145 & 0.27379 & 0.05467 \
0.44411 & - 0.33622 & - 0.10815
\end{array} \right]$$

Write the augmented matrix for the system. Do not solve the system. - 7x-2z =-9 2y+7z =9 7x+9y+4z =6

Solve the system. - ++=- +-=4 +-=

Graph the inequality. - $y \geq-2$ $Graph the inequality. - y \geq-2$

Find the value of the determinant. - $\left| \begin{array} { r r r } 5 & 5 & - 4 \\- 4 & - 3 & - 3 \\3 & - 2 & 0\end{array} \right|$

Find the values of the variables for which the statement is true, if possible. - $\left[ \begin{array} { l l l } - 8 & b & - 4 \end{array} \right] + \left[ \begin{array} { l l l } a & 9 & c \end{array} \right] = \left[ \begin{array} { l l l } 6 & 6 & - 5 \end{array} \right]$

Use a graphing calculator to solve the nonlinear system. Give x- and y-coordinates to the nearest hundredth. - -=7.82 x=2y-5

Find the inverse, if it exists, for the matrix. - $\left[ \begin{array} { l l l } 5 & - 2 & 4 \\10 & - 3 & 8 \\5 & - 1 & 4\end{array} \right]$

Solve the system by substitution. - 3x+7y =2 9y =30+2x

Graph the solution set of the system of inequalities. -

Perform the operation or operations when possible. - $\left[ \begin{array} { l l } 1 & 4 \end{array} \right] + \left[ \begin{array} { r } - 1 \\ 9 \end{array} \right]$

Graph the solution set of the system of inequalities. -

Give all solutions of the nonlinear system of equations, including those with nonreal complex components. - +xy+=19 x+y=2

Graph the inequality. - $x-y<-2$

Graph the solution set of the system of inequalities. -

Find the matrix product when possible. - $\left[ \begin{array} { r r r } - 5 & 7 & 9 \\- 1 & - 8 & 4\end{array} \right] \left[ \begin{array} { l } - 2 \\- 8 \\- 2\end{array} \right]$

Perform the operation or operations when possible. - $\left[ \begin{array} { r r } - 3 & 1 \\2 & 5\end{array} \right] + \left[ \begin{array} { l l } 6 & 2 \\3 & 3\end{array} \right]$

Use a graphing calculator to find the inverse of the matrix. Give five decimal places, if necessary. - $A = \left[ \begin{array} { c c c } 1.52 & 5.55 & 4 \\- 0.63 & 7.33 & 3.21 \\8.2 & 0.003 & - 2.8\end{array} \right]$

Equations and Inequalities

Graphs and Functions

Polynomial and Rational Functions

Inverse, Exponential, and Logarithmic Functions

Trigonometric Functions

The Circular Functions and Their Graphs

Trigonometric Identities and Equations

Applications of Trigonometry

Analytic Geometry

Further Topics in Algebra

Review of Basic Concepts

Filters

Exam 9: Systems and Matrices

Write the augmented matrix for the system. Do not solve the system. - 7x-2z =-9 2y+7z =9 7x+9y+4z =6

Solve the system. - ++=- +-=4 +-=

Graph the inequality. - y≥−2y \geq-2y≥−2

Find the value of the determinant. - ∣55−4−4−3−33−20∣\left| \begin{array} { r r r } 5 & 5 & - 4 \\- 4 & - 3 & - 3 \\3 & - 2 & 0\end{array} \right|​5−43​5−3−2​−4−30​​

Use a graphing calculator to solve the nonlinear system. Give x- and y-coordinates to the nearest hundredth. - -=7.82 x=2y-5

Find the inverse, if it exists, for the matrix. - [5−2410−385−14]\left[ \begin{array} { l l l } 5 & - 2 & 4 \\10 & - 3 & 8 \\5 & - 1 & 4\end{array} \right]​5105​−2−3−1​484​​

Solve the system by substitution. - 3x+7y =2 9y =30+2x

Graph the solution set of the system of inequalities. -

Perform the operation or operations when possible. - [14]+[−19]\left[ \begin{array} { l l } 1 & 4 \end{array} \right] + \left[ \begin{array} { r } - 1 \\ 9 \end{array} \right][1​4​]+[−19​]

Graph the solution set of the system of inequalities. -

Give all solutions of the nonlinear system of equations, including those with nonreal complex components. - +xy+=19 x+y=2

Graph the inequality. - x−y<−2x-y<-2x−y<−2

Graph the solution set of the system of inequalities. -

Find the matrix product when possible. - [−579−1−84][−2−8−2]\left[ \begin{array} { r r r } - 5 & 7 & 9 \\- 1 & - 8 & 4\end{array} \right] \left[ \begin{array} { l } - 2 \\- 8 \\- 2\end{array} \right][−5−1​7−8​94​]​−2−8−2​​

Perform the operation or operations when possible. - [−3125]+[6233]\left[ \begin{array} { r r } - 3 & 1 \\2 & 5\end{array} \right] + \left[ \begin{array} { l l } 6 & 2 \\3 & 3\end{array} \right][−32​15​]+[63​23​]

Equations and Inequalities

Graphs and Functions

Polynomial and Rational Functions

Inverse, Exponential, and Logarithmic Functions

Trigonometric Functions

The Circular Functions and Their Graphs

Trigonometric Identities and Equations

Applications of Trigonometry

Analytic Geometry

Further Topics in Algebra

Review of Basic Concepts

Filters

Graph the inequality. - $y \geq-2$ $Graph the inequality. - y \geq-2$

Find the value of the determinant. - $\left| \begin{array} { r r r } 5 & 5 & - 4 \\- 4 & - 3 & - 3 \\3 & - 2 & 0\end{array} \right|$

Find the inverse, if it exists, for the matrix. - $\left[ \begin{array} { l l l } 5 & - 2 & 4 \\10 & - 3 & 8 \\5 & - 1 & 4\end{array} \right]$

Perform the operation or operations when possible. - $\left[ \begin{array} { l l } 1 & 4 \end{array} \right] + \left[ \begin{array} { r } - 1 \\ 9 \end{array} \right]$

Graph the inequality. - $x-y<-2$

Find the matrix product when possible. - $\left[ \begin{array} { r r r } - 5 & 7 & 9 \\- 1 & - 8 & 4\end{array} \right] \left[ \begin{array} { l } - 2 \\- 8 \\- 2\end{array} \right]$

Perform the operation or operations when possible. - $\left[ \begin{array} { r r } - 3 & 1 \\2 & 5\end{array} \right] + \left[ \begin{array} { l l } 6 & 2 \\3 & 3\end{array} \right]$