Intermediate Algebra (11th edition)

41. 
    

43.length: 12 ft; width: 7 ft 45.$20; thousand or 800 calculators
47.

Section 11.5 (pages 667–668)

1.C 3.B 5.A

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9. 
   
   
   
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10. 
    
    
    
    27. 
        
        
        
        29. 
            
        
        
        
        
    
    
    
    


11. 
    
    
    
    33. 
        
        
        
        35. 
            
        
        
        
        
    
    
    
    


12. 
    
    
    
    39. 
        
    
    
    
    


13. 
    
    
    
    43. 10
    
    
    
    

–15 15

–10

10

–15 15

–10

0 1 x

–1

y

1

2

x^2 + 4y^2 ≥ 1

x ≥ 0

y ≥ 0

x

y

–2

4

0

4 x^2 – y^2 > 16

x < 0

x

y

–3

0

x < y^2 – 3

x < 0

x

y

x^2 + y^2 > 36

x ≥ 0

0

6

6

x

y

0

y ≤ –x^2

y ≥ x – 3

y ≤ –1

x < 1

x

y

2

x ≥ 0

y ≥ 0

x^2 + y^2 ≥ 4

x + y ≤ 5

0

x

y

–3

–4

0

3

y > x^2 – 4

y < –x^2 + 3

x

4 y

05

x ≤ 5

y ≤ 4

x

y

4

0

–5

5 x – 3y ≤ 15 3

x 4 x + y ≥ 4

y

2

–2

5

0

2 x + 5y < 10

x – 2y < 4

x

y

0

3

2

x ≤ –y^2 + 6y – 7

x

y

1

2

x^2 – 4 ≥ –4y^2

x

y

0

3

4

9 x^2 > 16y^2 + 144

x

y

0

–2

–2

y ≤ x^2 + 4x + 2

x

y

0

2

3

2 y^2 ≥ 8 – x^2

x

y

0

–2^2

y ê x^2 – 2

x

y

0

2

2

y^2 > 4 + x^2

4

5

51 2, - 32 , 1 - 3, 2 (^26) 45. (a) 6 (b) (c) (d)

47. (a) 0 (b) 2 (c) 6 (d) 12

Chapter 11 Review Exercises (pages 672–673)

1. 
   
   
   
   2. 
      
      
      
      3. 
         
      
      
      
      
   
   
   
   

4.

0 x

–3

3

–3 3

y

f(x) = x – 2

x

y

0 4

3

f(x) = √√x + 3

x

y

0 4

1

f(x) = ⏐x + 4⏐ f(x)=x^1 – 4

–8 –4

4

y

0 x

9

4

8

3

7

2

Answers to Selected Exercises A-29

10

–10

–10 10

10

–10

• 10 10

x

y

2

–4

2 x – y ÄÄ 4 5.

6.

7.

8.center: ; 1 - 3, 2 2 r= 4

1 x- 422 + 1 y- 222 = 36

1 x+ 122 + 1 y+ 322 = 25

1 x+ 222 + 1 y- 422 = 9

9.center: ; 10.center: ;

11.center: ;

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        14. 
            
        
        
        
        
    
    
    
    


13. 
    
    
    
    16. (a)348.2 ft (b)1787.6 ft
    
    
    
    


14. 
    
    
    
    18. 
        
        
        
        19. 
            
        
        
        
        
    
    
    
    

20.circle 21.parabola 22.hyperbola 23.ellipse 24.parabola

25.hyperbola 26. 27.

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    29. 
        
    
    
    
    


29. 
    
    
    
    31. 
        
    
    
    32. 
        

        33.0, 1, or 2 34.0, 1, 2, 3, or 4

        
        
    
    
    
    


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    36. 
        
        
        
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        40. 
            
        
        
        
        
    
    
    
    


32. 
    
    
    
    42. 
        
        
        
        43. 
            
        
        
        
        
    
    
    
    

x

y

1

3

x^2 + 9y^2 = 9

x

y

0

5

5

5

x^2 + y^2 = 25

3 x

y

0

2

• 1 =x 9
  2
  4

y^2

9 x^2 Ä 4 y^2 + 36

x^2 + y^2 Ä 16

4

3

x

y

x^0

y ⏐

x⏐ ÄÄ 2

⏐y⏐ > 1

4 x^2 + 9y^2 ÄÄ 36

2 x + 5y ÄÄ 10

3 x – y ÄÄ 6

x

y

(^05)
2
2
–6
x
y
–2 0
1
–3
y < –(x + 2)^2 + 1
2 x
y
0
4
4 x^2 + y^2 êê 16
4 x
y
3
9 x^2 êê 16 y^2 + 144
0
A^26 , -^23 B, A^26 ,^23 BF
A 22 , - 2 B, A 22 , 2BF EA- 26 , - 23 B,A- 26 , 23 B,
51 - 2, - 42 , 1 8, 1 (^26) EA- 22 , 2B, A- 22 , - (^2) B,
51 1, 2 2 , 1 - 5, 14 26 51 4, 2 2 , 1 - 1, - 326
51 6, - 92 , 1 - 2, - 526
x^2
625

• 
  

y^2

1875

= 1

x

y

–4^04

–4

x f(x) = – √16 –^ x^2

2

5

0

25 y– = 1

2

4

x^2

x

y

4

5

16 x– = 1

2

25

y^2

0

x^2

65,286,400

+

y^2

2,560,000

= 1

x

y

0

5

7

49 x+ = 1

2

25

y^2

x

y

0 4

4

x^2 + y^2 = 16

1 3, - 22 r= 5

1 4, 1 2 r= 2 1 - 1, - 52 r= 3

x

y

(^04)
3
16 x+ = 1
2
9
y^2