Intermediate Algebra (11th edition)

11. 
    
    
    
    13. 
        
        
        
        15. 
            
        
        
        
        
    
    
    
    


12. 
    
    
    
    19. 
        
        
        
        21. 
            
        
        
        
        
    
    
    
    


13. 
    
    
    
    25. 
        
        
        
        27. 
            
        
        
        
        
    
    
    
    


14. 
    
    
    
    31. 
        
        
        
        33. 
            
        
        
        
        
    
    
    
    


15. 
    
    
    
    37. 39.B; factoring
    
    
    
    

41.C; quadratic formula 43.A; factoring 45.D; quadratic formula

47. 
    
    
    
    49. 
        
        
        
        51. (a)Discriminant is 25, or ; solve
        
        
        
        
    
    
    
    

by factoring; (b)Discriminant is 44; use the quadratic

formula; 53. or 10 55. 16 57. 25

59. 
    
    
    
    61. 
        
        
        
        63. 
            
        
        
        
        
    
    
    
    

Section 9.3 (pages 519–522)

1.Multiply by the LCD, x. 3.Substitute a variable for

5.The proposed solution does not check. The solution set is 4.

7. 
   
   
   
   9. 
      
      
      
      11. 
          
          
          
          13. 
              
          
          
          
          
      
      
      
      
   
   
   
   


8. 
   
   
   
   17. 
       
       
       
       19. 
           
       
       
       
       
   
   
   
   


9. 
   
   
   
   23. 
       
       
       
       25. (a) mph
       
       
       
       
   
   
   
   

(b) mph 27.25 mph 29.50 mph 31.3.6 hr 33.Rusty:
25.0 hr; Nancy: 23.0 hr 35.3 hr; 6 hr 37. 2, 5 39. 3

41. 
    
    
    
    43. 9 45. 47. 49.
    
    
    
    


42. 
    
    
    
    53. 
        
        
        
        55. 
            
        
        
        
        
    
    
    
    


43. 
    
    
    
    59. 
        
        
        
        61. 
            
            
            
            63. 
                
            
            
            
            
        
        
        
        
    
    
    
    


44. 
    
    
    
    67. 
        
        
        
        69. 
            
            
            
            71. 3, 11
            
            
            
            
        
        
        
        
    
    
    
    


45. 25 75. 77.


46. 
    
    
    
    81. 
        
    
    
    
    


47. or 85.

Summary Exercises on Solving Quadratic

Equations (page 522)

1.square root property 2.factoring 3.quadratic formula
4.quadratic formula 5.factoring 6.square root property

C=

5

9

W= 1 F- 322

P

2

W= -L

P- 2 L

2

,

u1, 

26

2

 iv

39 - 265

2

u v

39 + 265

2

,

u- 235 , - E^43 , 49 F

234

2

5 6 v

u 5 6

26

3

, 

1

2

E- 31 , 61 F E- 21 , 3F v

E-^163 , - 2 F 5 - 8, 1 6 5 - 64, 27 6 E1,  278 F

E1,  23 F E2,  223 F 5 - 6, - 56

E^89 F 56 E 52 F 5 - 26 5 2,  56

5 6 56

120 +t 2

u 120 - t 2

• 1  25
  4
  u v
  2  222
  3
  v

u E-^83 , - 1 F

• 1  213
  2
  E-^117 , 0F v

5 - 2, 7 6 5 - 4, 7 6 E-^23 , 1F E- 1714 , 5F

• 1 56

x^2 +x.

b=^445 ; 103 5 - 86 556

u - 10

7  211

2

v

E-3, -^43 F

E- 57 F E-^13 , 2F^52

u- E^12 ^14 i (^) F
2
3

22
3
i v
u
1
2

26
2
u E 3 i (^25) F i v
3
2

215
2
i v
u

• 3  257
  8
  u v


• 4  291
  3
  u v
  1  229
  2
  v

u E- 1  (^322) F

• 2  210
  2
  E^1 ^25 F^ v

u

• 1  27
  3
  u v


• 1  22
  2
  E^5 ^27 F^ v

7. 
   
   
   
   8. 
      
      
      
      9. 
         
         
         
         10. 
             
         
         
         
         
      
      
      
      
   
   
   
   


8. 
   
   
   
   12. 
       
       
       
       13. 
           
           
           
           14. 
               
           
           
           
           
       
       
       
       
   
   
   
   


9. 
   
   
   
   16. 
       
       
       
       17. 
           
           
           
           18. 
               
           
           
           
           
       
       
       
       
   
   
   
   


10. 
    
    
    
    20. 
        
        
        
        21. 
            
        
        
        
        
    
    
    
    


11. 
    
    
    
    23. 
        
        
        
        24. 
            
            
            
            25. 
                
            
            
            
            
        
        
        
        
    
    
    
    


12. 
    
    
    
    27. 
        
        
        
        28. 
            
            
            
            29. 
                
            
            
            
            
        
        
        
        
    
    
    
    


13. 3 31. 32.

Section 9.4 (pages 527–531)

1.Find a common denominator, and then multiply both sides by the

common denominator. 3.Write it in standard form (with 0 on one

side, in decreasing powers of w). 5.

7. 
   
   
   
   9. 
      
      
      
      11. 
          
      
      
      
      
   
   
   
   


8. 
   
   
   
   15. 
       
       
       
       17. 
           
       
       
       
       
   
   
   
   


9. 
   
   
   
   21. 
       
       
       
       23. 
           
       
       
       
       
   
   
   
   


10. or 27.

29.7.9, 8.9, 11.9 31.eastbound ship: 80 mi; southbound ship: 150 mi

33.8 in., 15 in., 17 in. 35.length: 24 ft; width: 10 ft 37.2 ft

39.7 m by 12 m 41.20 in. by 12 in. 43.1 sec and 8 sec 45.2.4 sec

and 5.6 sec 47.9.2 sec 49.It reaches its maximumheight at 5 sec

because this is the only time it reaches 400 ft. 51.$0.80 53.0.035,

or 3.5% 55.5.5 m per sec 57.5 or 14 59. (a)$420 billion

(b)$420 billion; They are the same. 61.2004; The graph indicates

that spending first exceeded $400 billion in 2005. 63. 9

65.domain: range:

Section 9.5 (pages 537–540)

1. (a)B (b)C (c)A (d)D 3. 0, 0 5. 0, 4 7. 1, 0


2. 
   
   
   
   11. 5, 6 13.down; wider 15.up; narrower
       17.down; narrower 19. (a)D (b)B (c)C (d)A
   
   
   
   


3. 
   
   
   
   23. 
       
       
       
       25. 
           
       
       
       
       
   
   
   
   

x

y

–3 03

–7

2

f(x) = –x^2 + 2

x

y

3

0

2

f(x) = x^2 – 1

x

y

01

–2

f(x) = –2x^2

1 - 3, - 42 1 2

1 2 1 2 1 2

y

–2 0 2 x

8

f(x) = 2 x 2

1 - q, q 2 ; 3 0, q 2

I=

• cR 2 c^2 R^2 - 4 cL
  2 cL
  r=-

2 pc

3

r=

5 pc

4

R=

E^2 - 2 prE 2 E^2 - 4 pr

2 p

r=

 2 Sp

2 p

/=

p^2 g

k

h=

D^2

k

t=

• B 2 B^2 - 4 AC
  2 A
  r=
   23 pVh
  ph

v=

 2 kAF

F

d=

 2 skI

I

t=

 2 dk

k

m= 2 p^2 - n^2

u E-^13 ,^16 F

1

6



247

6

56 iv

u 1 

23

3

E- 32 , 2F 5 - 4, 9 6 5  136 i v

u- E 23 F E^23 F E 622 F

23175

5

, 1v

u-

1

2



23

2

u iv

1  25

4

E 22 ,  27 F v

u E^45 , 3F

• 3  222
  2
  E^12 , 2F 5 1,  36 v

u E 2 i 23 F

2  22

2

E- 23 , 4F E-3, 31 F v

E 27 F E-^32 , 35 F E- 3  25 F 5 - 2, 8 6

Answers to Selected Exercises A-21