Page 605 - Basic College Mathematics with Early Integers

582 C HAPTE R 8 I INTRODUCTION TO ALGEBRA

Mixed Practice Solve. See Examples 1 through 8.

27. -7x = 0 28. -20y = 0 29. 0.4 =-8z 30. 0.5 =-20x

8 3 7 2 3 6 6 1
31. t =- 32. r =- 33. - x =- 34. - y =-
5 8 4 7 5 15 7 14

35. -3.6 =-0.9u + 0.3u 36. -5.4 =-1.4y + 1.3y 37. 5 - 5 = 2x + 7x

38. 12 + 1-122 = 7x + 8x 39. -42 + 20 =-2x + 13x 40. -4y + 9y =-20 + 15

41. -3x - 3x = 50 - 2 42. 5y - 9y =-14 + (-14) 43. 23x - 25x = 7 - 9

1 5 1 4
44. 6x - 8x = 12 - 22 45. x - x = 20 - 47 46. x - x = 10 - 19
4 8 2 5

x x x y
47. 18 - 11 = 48. 14 - 9 = 49. = 1 - (-6) 50. = 6 - (-1)
5 12 -4 -6

Review

Evaluate each expression when x = 5. See Section 8.1.

x - 3 3x + 5 2x - 1
51. 3x + 10 52. 40x 53. 54. 7x - 20 55. 56.
2 x - 7 x - 8

The trumpeter swan is the largest waterfowl in the United States.Although it was nearly extinct at one time, recent
conservation efforts have been succeeding. Use the bar graph to answer Exercises 57 through 60. See Section 7.1.

57. During what year shown is the number of Trumpeter Swan Population
trumpeter swans the greatest? in North America

2010*
58. During what year shown is the number of
2005
trumpeter swans the least?
2000
Year 1995
59. Use the length of the bar to estimate the 1990
number of trumpeter swans in 2005. 1985
1980
1975 Copyright 2012 Pearson Education, Inc.
60. Describe any trends shown in this graph.
0 5000 10,000 15,000 20,000 25,000 30,000 35,000 40,000 45,000 50,000
Number of Swans
Source: U.S. Fish and Wildlife Service; the year 2010 is projected