Beginning Algebra, 11th Edition

14. ; 15. ;

3 x + 2y = 8

y

0 x

4

8

3

y = 2x + 5

5

0

-^52
x

y

A- 25 , 0B 1 0, 5 2 A 38 , 0B 1 0, 4 2

Answers to Selected Exercises A-9

56.no x-intercept; ; 0 57. 58.

59. 
    
    
    
    60. 
        
    
    
    
    


60. 
    
    
    
    62. 
        
    
    
    
    

63.Since the graph rises from left to right, the slope is positive.

64. 
    
    
    
    65. 66.2003: 41.7; 2004: 42.2; 2005: 42.7; 2006: 43.2
    
    
    
    

Chapter 3 Test (pages 244–245)

[3.1]1. 2.no [3.2]3.To find the x-intercept, let
and to find the y-intercept, let x=0.

• 6, -10, - 5 y=0,

1 2002, 41.2 2 , 1 2007, 43.7 2 y=0.5x-959.8

y < –4x

0

y

x

x – 2y ≤ 6

0

y

x

y=- 47 x-^237 y=- 5

y – 5 = 0

0

y

x

1 0, 5 2 y=- 41 x- 45 y=- 3 x+ 30

54. ; ;

y = –2x – 5

0

y

x

–5

5

• 2

A- 25 , 0B 1 0, - 52 - 2 55. ; ;

x + 3y = 0

0

1

y

–3 x

1 0, 0 21 0, 0 2 - (^13)

17. 18.undefined 19. 3 20. 0 21. 22. 23.


18. (a) 2 (b) 25.parallel 26.perpendicular 27.neither


19. 
    
    
    
    29. 
        
        
        
        30. 
            
            
            
            31. 
                
            
            
            
            
        
        
        
        
    
    
    
    


20. 
    
    
    
    33. 
        
        
        
        34. 
            
            
            
            35. ;
                It is not possible to express this equation in the form
            
            
            
            
        
        
        
        
    
    
    
    


21. 
    
    
    
    37. 
        
        
        
        38. 
            
        
        
        
        
    
    
    
    

39.not a function; domain: ; range:
40.function; domain: ; range:
41.not a function 42.function 43.function 44.function

45. (a) 8 (b) 46. (a) 7 (b) 1 47. (a) 5 (b) 2 48.A
    49.C, D 50.A, B, D 51.D 52.C 53.B
    
    
    • 1
    
    
    
    

5 8, 7, 6, 5, 4 6 5 3, 4, 5, 6, 7 6

5 - 2, 0, 2 6 5 4, 8, 5, 3 6

x

y

0

x – 2y ≥ 0

x

y

0

2 x – 3y > –6

x

y

0

3 x + 5y > 9

y=mx+b.

y=-^34 x- 41 y=- 14 x+ 23 y= 1 x= 31

y=-x+^23 y=- 12 x+ 4 y=x- 7 y= 32 x+^143

1

3

3

• 2
  1
  3

3

• (^2)
  1
  2

16. 
    

    x + 2y = – 4
    –4 –2^0 x
    y
    1 - 4, 0 2 ; 1 0, - 22
    4.x-intercept: ;
    y-intercept:
    x
    y
    0
    3 x + y = 6
    6
    2
    1 0, 6 2
    1 2, 0 2
    [3.5]17. 18.
    [3.1–3.4]19.The slope is negative, since sales are decreasing.

    
    


17. 
    

    ;
    21.174 thousand; The equation gives a good approximation of the actual
    sales. 22.In 2007, worldwide snowmobile sales were 160 thousand.
    [3.6]23. (a)not a function (b)function; domain: ;
    range: 24.not a function 25. 1

    
    

Chapters 1– 3 Cumulative Review Exercises

(page 246)

[1.1]1. 2. 6 [1.5]3. 7 [1.6]4.

[1.2–1.6]5.true 6. [1.7]7.distributive property

[1.8]8. [2.5]9. [2.3]10. 11.

[2.6]12. [2.8] 13.

14. 
    
    
    
    15. 
        
    
    
    
    

[2.4]16.high school diploma: $30,732; bachelor’s degree: $50,856

[1.1, 2.6]17. (a)$7000(b)$10,000 18.about $30,000

[3.2]19. ; [3.3]20.

[3.2]21. [3.3]22.perpendicular

[3.4]23. 24.

SYSTEMS OF LINEAR EQUATIONS

AND INEQUALITIES

Connections (page 253) 1. 2.

3.

Section 4.1 (pages 253–257)

1.A; The ordered-pair solution must be in quadrant II, and

1 - 4, - 42 is in quadrant III. 3.no 5.yes 7.yes 9.no

51 1.5, -1.5 26

51 - 1, 5 26 51 0.25, -0.5 26

4

y= 3 x- 11 y= 4

–3x + 4y = 12

3

–4 0

y

x

3

1 - 4, 0 21 0, 3 (^24)
–4 0
1 - q, - 44
00
1 0, q 2
–2.6–2.6–1–1 00
5 - 136 1 - 2.6, q 2
h= 5 - 16 526
3 V

• 
  

  p+ (^2) pr 2

  
  


• 
  

  43

  
  

73

18 , or 4

1

18

301

40 , or 7^

21

40

526

5 0, 1, 2 6

1 0, 209 2 , 1 7, 160 2 y=- 7 x+ 209

3 x – y > 0

0

y

x x

y

0

x + y ≤ 3

6.x-intercept: ;

y-intercept: none

x + 3 = 0

0

y

x

1 - 3, 0 2

8.x-intercept: ;

y-intercept:

x – y = 4

–4

0 4

y

x

1 0, - 42

1 4, 0 2 [3.3]9. 10. 11.undefined

12. 0 13.
    [3.4]14. 15.
    16.y=- 9 x+ 12

y= 2 x+ 6 y= 25 x- 4

5

2

• 83 - 2

7.x-intercept: none;

y-intercept:

y = 1

0

y

x

1 0, 1 2

5.x-intercept: ;

y-intercept:

y – 2x = 0

2

1

y

x

1 0, 0 2

1 0, 0 2