1. Adding Real Numbers pages 27–30 Exercises 1. 6 + (–3); 3 12. –42
ALGEBRA 1 LESSON 1-4
pages 27–30  Exercises
(–3); 3
2. –1 + (–2); –3
3. –5 + 7; 2
(–4); –1
5. 15
6. –11
7. –19
9. –4
10. 5
11. –8 1 6
12. –42
14. –0.65
15. –7.49
17.
18. –
19. 6
20. –6
21. 0
22. –
23. 5
24. –
25. – = –35, 35 ft
below the surface
(–5) = 3, 3 yd gain
27. – = 7, 7°F
29. –1.7
31. –8.7 13 14 14 15 8 9 3 16 1 8 13 18
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2. 36–37. Choices of variable may vary. 36. c = change in temp., –8 + c
Adding Real Numbers
ALGEBRA 1 LESSON 1-4
38.
39.
40.
41.
42. –2.7
43. –13
33. –5.6
35. –12.6
36–37. Choices of variable may vary.
36. c = change in temp., –8 + c
a. –1°F
b. –11°F
c. 11°F
37. c = change in amount
of money, 74 + c
a. $92
b. $45
c. $27
–1 1.4 – 19 24
45. 11
46. 4
47. –3
48. –18.53
49. –20.83
50. –1.72
51. –
52. –5
54. 4
55. –8.8
–18.2
11.6
19.1 22 35 25
–12 17 60
1.8 22
– 7 11
120 1 2 1 3
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3. is positive, while the sum of 227 and –319 is negative.
Adding Real Numbers
ALGEBRA 1 LESSON 1-4
million people
million people
58. Weaving; add the
numbers in each column.
59. a. =
b. 0.23
c. about 23%
60. 0
61. –2
62. 1
63. –5
64. 7
65. 5
66. –1
67. 1
68. The sum of –227 and 319;
the sum of –227 and 319
is positive, while the sum
of 227 and –319 is negative.
69. Answers may vary. Sample:
Although 20 and –20 are
opposite numbers, there is
no such thing as opposite
temperatures.
70. –0.3
71. –13.7
72. –0.6
75. –1.9
76. +2
100
442 50
221
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4. 77. Answers may vary. Sample:
Adding Real Numbers
ALGEBRA 1 LESSON 1-4
77. Answers may vary. Sample:
78. The matrices are not the
same size, so they can’t
be added.
79. No; time and temperature
are different quantities and
can’t be added.
80. a.
82. a. 4
b. –4
80. (continued) b.
c. 4 employees
d. 10 employees
e. Answers may vary. Sample:
Multiply the entries in each
column by the appropriate
hourly wage, then by 8, and
then add all entries to find
the total wages.
f. $3230
81. $7
2 0 1 –
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5. Adding Real Numbers 83. 84. 85. 86. – 87. 88. – 89. 8 32 –27 20 6 0
ALGEBRA 1 LESSON 1-4
83.
84.
85.
86. –
87.
88. –
89.
8 32 –27
1 –1
2 1 1 4 2 w 10 c
90. –
91.
92.
93.
94. Pos.; if m is neg.,
–m is pos. and the
sum of two pos.
is pos.
95. Neg.; if n is pos.,
–n is neg. and the
sum of two neg.
is neg.
96. Pos.; if m is neg.,
97. Zero; sum of neg.
and pos. is the
difference of the
abs. values.
|n| = |m| so |n| – |m| = 0.
98. zero; n + (–m) = n + (–n) = 0
99. B
100. F
101. D
102. F
103. C
104. H
105. <
106. =
111. 9
107. <
108. >
109. >
110. = x 12 t 6
–3m + 1 m 9
58a 21 2b
1-4