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Developmental Mathematics

Elayn Martin-Gay

Chapter 8

Real Numbers and Introduction to Algebra - all with Video Answers

Educators


Section 1

Symbols and Sets of Numbers

00:31

Problem 1

Objectives A C Mixed Practice Insert $<,>$, or $=$ in the space between the paired numbers to make each statement true. See Examples 1 through 6 and 10.
410

Stephanie Carter
Stephanie Carter
Numerade Educator
00:31

Problem 2

Objectives A C Mixed Practice Insert $<,>$, or $=$ in the space between the paired numbers to make each statement true. See Examples 1 through 6 and 10.
85

Stephanie Carter
Stephanie Carter
Numerade Educator
00:31

Problem 3

Objectives A C Mixed Practice Insert $<,>$, or $=$ in the space between the paired numbers to make each statement true. See Examples 1 through 6 and 10.
73

Stephanie Carter
Stephanie Carter
Numerade Educator
00:31

Problem 4

Objectives A C Mixed Practice Insert $<,>$, or $=$ in the space between the paired numbers to make each statement true. See Examples 1 through 6 and 10.
915

Stephanie Carter
Stephanie Carter
Numerade Educator
00:40

Problem 5

Objectives A C Mixed Practice Insert $<,>$, or $=$ in the space between the paired numbers to make each statement true. See Examples 1 through 6 and 10.
$6.26 \quad 6.26$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:38

Problem 6

Objectives A C Mixed Practice Insert $<,>$, or $=$ in the space between the paired numbers to make each statement true. See Examples 1 through 6 and 10.
$1.13 \quad 1.13$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:31

Problem 7

Objectives A C Mixed Practice Insert $<,>$, or $=$ in the space between the paired numbers to make each statement true. See Examples 1 through 6 and 10.
$0 \quad 7$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:31

Problem 8

Objectives A C Mixed Practice Insert $<,>$, or $=$ in the space between the paired numbers to make each statement true. See Examples 1 through 6 and 10.
200

Stephanie Carter
Stephanie Carter
Numerade Educator
00:12

Problem 9


The freezing point of water is $32^{\circ}$ Fahrenheit. The boiling point of water is $212^{\circ}$ Fahrenheit. Write an inequality statement using $<$ or $>$ comparing the numbers 32 and 212.

Ian Maurer
Ian Maurer
Numerade Educator
00:12

Problem 10

The freezing point of water is $0^{\circ}$ Celsius. The boiling point of water is $100^{\circ}$ Celsius. Write an inequality statement using $<$ or $>$ comparing the numbers 0 and 100.

Ian Maurer
Ian Maurer
Numerade Educator
00:37

Problem 11

An angle measuring $30^{\circ}$ and an angle measuring $45^{\circ}$ are shown. Write an inequality statement using $\leq$ or $\gtrsim$ comparing the numbers 30 and 45 .

Stephanie Carter
Stephanie Carter
Numerade Educator
00:51

Problem 12

The sum of the measures of the angles of a parallelogram is $360^{\circ}$. The sum of the measures of the angles of a triangle is $180^{\circ}$. Write an inequality statement using $\leq$ or $\geqq$ comparing the numbers 360 and 180 .

Stephanie Carter
Stephanie Carter
Numerade Educator
00:34

Problem 13

Determine whether each statement is true or false. See Examples 1 through 6 and 10.
$11 \leq 11$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:46

Problem 14

Determine whether each statement is true or false. See Examples 1 through 6 and 10.
$8 \geq 9$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:40

Problem 15

Determine whether each statement is true or false. See Examples 1 through 6 and 10.
$-11>-10$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:40

Problem 16

Determine whether each statement is true or false. See Examples 1 through 6 and 10.
$-16>-17$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:24

Problem 17

Determine whether each statement is true or false. See Examples 1 through 6 and 10.
$5.092<5.902$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:04

Problem 18

Determine whether each statement is true or false. See Examples 1 through 6 and 10.
$1.02>1.021$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:33

Problem 19

Determine whether each statement is true or false. See Examples 1 through 6 and 10.
$\frac{9}{10} \leq \frac{8}{9}$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:33

Problem 20

Determine whether each statement is true or false. See Examples 1 through 6 and 10.
$\frac{4}{5} \leq \frac{9}{11}$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:29

Problem 21

Rewrite each inequality so that the inequality symbol points in the opposite direction and the resulting statement has the same meaning as the given one. See Examples 1 through 6 and 10.
$25 \geq 20$

Ian Maurer
Ian Maurer
Numerade Educator
00:55

Problem 22

Rewrite each inequality so that the inequality symbol points in the opposite direction and the resulting statement has the same meaning as the given one. See Examples 1 through 6 and 10.
$-13 \leq 13$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:46

Problem 23

Rewrite each inequality so that the inequality symbol points in the opposite direction and the resulting statement has the same meaning as the given one. See Examples 1 through 6 and 10.
$0<6$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:44

Problem 24

Rewrite each inequality so that the inequality symbol points in the opposite direction and the resulting statement has the same meaning as the given one. See Examples 1 through 6 and 10.
$5>3$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:55

Problem 25

Rewrite each inequality so that the inequality symbol points in the opposite direction and the resulting statement has the same meaning as the given one. See Examples 1 through 6 and 10.
$-10>-12$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:50

Problem 26

Rewrite each inequality so that the inequality symbol points in the opposite direction and the resulting statement has the same meaning as the given one. See Examples 1 through 6 and 10.
$-4<-2$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:40

Problem 27

Objectives B C Mixed Practice-Translating Write each sentence as a mathematical statement. See Example 7.
Seven is less than eleven.

Stephanie Carter
Stephanie Carter
Numerade Educator
00:40

Problem 28

Objectives B C Mixed Practice-Translating Write each sentence as a mathematical statement. See Example 7.
Twenty is greater than two.

Stephanie Carter
Stephanie Carter
Numerade Educator
00:23

Problem 29

Objectives B C Mixed Practice-Translating Write each sentence as a mathematical statement. See Example 7.
Five is greater than or equal to four.

Ian Maurer
Ian Maurer
Numerade Educator
00:31

Problem 30

Objectives B C Mixed Practice-Translating Write each sentence as a mathematical statement. See Example 7.
Negative ten is less than or equal to thirty-seven.

Ian Maurer
Ian Maurer
Numerade Educator
00:35

Problem 31

Objectives B C Mixed Practice-Translating Write each sentence as a mathematical statement. See Example 7.
Fifteen is not equal to negative two.

Ian Maurer
Ian Maurer
Numerade Educator
00:27

Problem 32

Objectives B C Mixed Practice-Translating Write each sentence as a mathematical statement. See Example 7.
Negative seven is not equal to seven.

Ian Maurer
Ian Maurer
Numerade Educator
01:10

Problem 33

Use integers to represent the value(s) in each statement. See Example 8.
The highest elevation in California is Mt. Whitney, with an altitude of 14,494 feet. The lowest elevation in California is Death Valley, with an altitude of 282 feet below sea level. (Source: U.S. Geological Survey)

Stephanie Carter
Stephanie Carter
Numerade Educator
00:51

Problem 34

Use integers to represent the value(s) in each statement. See Example 8.
Driskill Mountain, in Louisiana, has an altitude of 535 feet. New Orleans, Louisiana, lies 8 feet below sea level. (Source: U.S. Geological Survey)

Stephanie Carter
Stephanie Carter
Numerade Educator
00:37

Problem 35

Use integers to represent the value(s) in each statement. See Example 8.
The number of graduate students at the University of Texas at Austin was 28,288 fewer than the number of undergraduate students. (Source: University of Texas at Austin, 2016)

Malisa Brill
Malisa Brill
Numerade Educator
01:12

Problem 36

Use integers to represent the value(s) in each statement. See Example 8.
The number of students admitted to the class of 2020 at UCLA was 79,647 fewer students than the number that had applied. (Source: UCLA, 2016)

Nicole C
Nicole C
Numerade Educator
00:52

Problem 37

Use integers to represent the value(s) in each statement. See Example 8.
A community college student deposited $$\$ 475$$ in her savings account. She later withdrew $$\$ 195$$.

Stephanie Carter
Stephanie Carter
Numerade Educator
00:27

Problem 38

Use integers to represent the value(s) in each statement. See Example 8.
A deep-sea diver ascended 17 feet and later descended 15 feet.

Ian Maurer
Ian Maurer
Numerade Educator
01:10

Problem 39

Graph each set of numbers on the number line. See Example 9.
$-4,0,2,-2$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:16

Problem 40

Graph each set of numbers on the number line. See Example 9.
$-3,0,1,-5$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:43

Problem 41

Graph each set of numbers on the number line. See Example 9.
$-2,4, \frac{1}{3},-\frac{1}{4}$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:46

Problem 42

Graph each set of numbers on the number line. See Example 9.
$-5,3,-\frac{1}{3}, \frac{7}{8}$

Stephanie Carter
Stephanie Carter
Numerade Educator
02:39

Problem 43

Graph each set of numbers on the number line. See Example 9.
$-4.5, \frac{7}{4}, 3.25,-\frac{3}{2}$

Stephanie Carter
Stephanie Carter
Numerade Educator
02:42

Problem 44

Graph each set of numbers on the number line. See Example 9.
$4.5,-\frac{9}{4}, 1.75,-\frac{7}{2}$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:22

Problem 45

Tell which set or sets each number belongs to: natural numbers, whole numbers, integers, rational numbers, irrational numbers, or real numbers. See Example 11.
0

Ian Maurer
Ian Maurer
Numerade Educator
00:48

Problem 46

Tell which set or sets each number belongs to: natural numbers, whole numbers, integers, rational numbers, irrational numbers, or real numbers. See Example 11.
$\frac{1}{4}$

Ian Maurer
Ian Maurer
Numerade Educator
01:02

Problem 47

Tell which set or sets each number belongs to: natural numbers, whole numbers, integers, rational numbers, irrational numbers, or real numbers. See Example 11.
-7

Stephanie Carter
Stephanie Carter
Numerade Educator
00:54

Problem 48

Tell which set or sets each number belongs to: natural numbers, whole numbers, integers, rational numbers, irrational numbers, or real numbers. See Example 11.
$-\frac{1}{7}$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:08

Problem 49

Tell which set or sets each number belongs to: natural numbers, whole numbers, integers, rational numbers, irrational numbers, or real numbers. See Example 11.
265

Stephanie Carter
Stephanie Carter
Numerade Educator
01:13

Problem 50

Tell which set or sets each number belongs to: natural numbers, whole numbers, integers, rational numbers, irrational numbers, or real numbers. See Example 11.
7941

Stephanie Carter
Stephanie Carter
Numerade Educator
00:37

Problem 51

Tell which set or sets each number belongs to: natural numbers, whole numbers, integers, rational numbers, irrational numbers, or real numbers. See Example 11.
$\frac{2}{3}$

Ian Maurer
Ian Maurer
Numerade Educator
01:37

Problem 52

Tell which set or sets each number belongs to: natural numbers, whole numbers, integers, rational numbers, irrational numbers, or real numbers. See Example 11.
$\sqrt{3}$

Ian Maurer
Ian Maurer
Numerade Educator
00:55

Problem 53

Determine whether each statement is true or false.
Every rational number is also an integer.

Stephanie Carter
Stephanie Carter
Numerade Educator
00:19

Problem 54

Determine whether each statement is true or false.
Every natural number is positive.

Brandon Fox
Brandon Fox
Numerade Educator
00:35

Problem 55

Determine whether each statement is true or false.
0 is a real number.

Stephanie Carter
Stephanie Carter
Numerade Educator
00:45

Problem 56

Determine whether each statement is true or false.
$\frac{1}{2}$ is an integer.

Stephanie Carter
Stephanie Carter
Numerade Educator
01:10

Problem 57

Determine whether each statement is true or false.
Every negative number is also a rational number.

Stephanie Carter
Stephanie Carter
Numerade Educator
01:13

Problem 58

Determine whether each statement is true or false.
Every rational number is also a real number.

Ian Maurer
Ian Maurer
Numerade Educator
00:37

Problem 59

Determine whether each statement is true or false.
Every real number is also a rational number.

Ian Maurer
Ian Maurer
Numerade Educator
00:52

Problem 60

Determine whether each statement is true or false.
Every whole number is an integer.

Rebecca Dias
Rebecca Dias
Numerade Educator
00:31

Problem 61

Objective D Find each absolute value. See Example 12.
$|8.9|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:28

Problem 62

Objective D Find each absolute value. See Example 12.
$|11.2|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:34

Problem 63

Objective D Find each absolute value. See Example 12.
$|-20|$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:11

Problem 64

Objective D Find each absolute value. See Example 12.
$|-17|$

Anas Venkitta
Anas Venkitta
Numerade Educator
00:29

Problem 65

Objective D Find each absolute value. See Example 12.
$\left|\frac{9}{2}\right|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:31

Problem 66

Objective D Find each absolute value. See Example 12.
$\left|\frac{10}{7}\right|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:37

Problem 67

Objective D Find each absolute value. See Example 12.
$\left|-\frac{12}{13}\right|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:37

Problem 68

Objective D Find each absolute value. See Example 12.
$\left|-\frac{1}{15}\right|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:15

Problem 69

Insert $<,>$, or $=$ in the appropriate space to make each statement true. See Examples 12 and 13.
$|-5| \quad-4$

Ian Maurer
Ian Maurer
Numerade Educator
01:05

Problem 70

Insert $<,>$, or $=$ in the appropriate space to make each statement true. See Examples 12 and 13.
$|-12|$ $|0|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:55

Problem 71

Insert $<,>$, or $=$ in the appropriate space to make each statement true. See Examples 12 and 13.
$\left|-\frac{5}{8}\right| \quad\left|\frac{5}{8}\right|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:24

Problem 72

Insert $<,>$, or $=$ in the appropriate space to make each statement true. See Examples 12 and 13.
$\left|\frac{2}{5}\right| \quad\left|-\frac{2}{5}\right|$

Ian Maurer
Ian Maurer
Numerade Educator
00:59

Problem 73

Insert $<,>$, or $=$ in the appropriate space to make each statement true. See Examples 12 and 13.
$|-2| \quad|-2.7|$

Stephanie Carter
Stephanie Carter
Numerade Educator
01:01

Problem 74

Insert $<,>$, or $=$ in the appropriate space to make each statement true. See Examples 12 and 13.
$|-5.01| \quad|-5|$

Stephanie Carter
Stephanie Carter
Numerade Educator
00:16

Problem 75

Insert $<,>$, or $=$ in the appropriate space to make each statement true. See Examples 12 and 13.
$|0| \quad|-8|$

Ian Maurer
Ian Maurer
Numerade Educator
00:22

Problem 76

Insert $<,>$, or $=$ in the appropriate space to make each statement true. See Examples 12 and 13.
$|-12| \frac{-24}{2}$

Ian Maurer
Ian Maurer
Numerade Educator
01:07

Problem 77

Perform each indicated operation. See Section 1.9.
$90+12^2-5^3$

Alekhya Bhupalam
Alekhya Bhupalam
Numerade Educator
01:07

Problem 78

Perform each indicated operation. See Section 1.9.
$3 \cdot(7-4)+2 \cdot 5^2$

Alekhya Bhupalam
Alekhya Bhupalam
Numerade Educator
01:30

Problem 79

Perform each indicated operation. See Section 1.9.
$12 \div 4-2+7$

Derrick Hanson
Derrick Hanson
Numerade Educator
00:50

Problem 80

Perform each indicated operation. See Section 1.9.
$12 \div(4-2)+7$

Ethan Somes
Ethan Somes
Numerade Educator
00:26

Problem 81

The bar graph shows corn production from the top six corn-producing states. (Source: National Agricultural Statistics Service)
Write an inequality comparing the corn production in Illinois with the corn production in Iowa.

Kerry Thornton-Genova
Kerry Thornton-Genova
Numerade Educator
00:26

Problem 82

The bar graph shows corn production from the top six corn-producing states. (Source: National Agricultural Statistics Service)
Write an inequality comparing the corn production in Minnesota with the corn production in South Dakota.

Kerry Thornton-Genova
Kerry Thornton-Genova
Numerade Educator
00:26

Problem 83

The bar graph shows corn production from the top six corn-producing states. (Source: National Agricultural Statistics Service)
Determine the difference between the corn production in Nebraska and the corn production in Illinois.

Kerry Thornton-Genova
Kerry Thornton-Genova
Numerade Educator
01:13

Problem 84

The bar graph shows corn production from the top six corn-producing states. (Source: National Agricultural Statistics Service)
Determine the difference between the corn production in Indiana and the corn production in Minnesota.

Breanna Ollech
Breanna Ollech
Numerade Educator
01:23

Problem 85

The apparent magnitude of a star is the measure of its brightness as seen by someone on Earth. The smaller the apparent magnitude, the brighter the star. Below, the apparent magnitudes of some stars are listed. Use this table to answer Exercises 85 through 90.
The apparent magnitude of the sun is -26.7 . The apparent magnitude of the star Arcturus is -0.04 . Write an inequality statement comparing the numbers -0.04 and -26.7 .

Malisa Brill
Malisa Brill
Numerade Educator
00:36

Problem 86

The apparent magnitude of a star is the measure of its brightness as seen by someone on Earth. The smaller the apparent magnitude, the brighter the star. Below, the apparent magnitudes of some stars are listed. Use this table to answer Exercises 85 through 90.
The apparent magnitude of Antares is 0.96 . The apparent magnitude of Spica is 0.98 . Write an inequality statement comparing the numbers 0.96 and 0.98 .

Ian Maurer
Ian Maurer
Numerade Educator
00:40

Problem 87

The apparent magnitude of a star is the measure of its brightness as seen by someone on Earth. The smaller the apparent magnitude, the brighter the star. Below, the apparent magnitudes of some stars are listed. Use this table to answer Exercises 85 through 90.
Which is brighter, the sun or Arcturus?

Ian Maurer
Ian Maurer
Numerade Educator
00:50

Problem 88

The apparent magnitude of a star is the measure of its brightness as seen by someone on Earth. The smaller the apparent magnitude, the brighter the star. Below, the apparent magnitudes of some stars are listed. Use this table to answer Exercises 85 through 90.
Which is dimmer, Antares or Spica?

Ian Maurer
Ian Maurer
Numerade Educator
00:41

Problem 89

The apparent magnitude of a star is the measure of its brightness as seen by someone on Earth. The smaller the apparent magnitude, the brighter the star. Below, the apparent magnitudes of some stars are listed. Use this table to answer Exercises 85 through 90.
Which star listed is the brightest?

Ian Maurer
Ian Maurer
Numerade Educator
00:41

Problem 90

The apparent magnitude of a star is the measure of its brightness as seen by someone on Earth. The smaller the apparent magnitude, the brighter the star. Below, the apparent magnitudes of some stars are listed. Use this table to answer Exercises 85 through 90.
Which star listed is the dimmest?

Ian Maurer
Ian Maurer
Numerade Educator
01:16

Problem 91

In your own words, explain how to find the absolute value of a number.

Ian Maurer
Ian Maurer
Numerade Educator
00:50

Problem 92

Give an example of a real-life situation that can be described with integers but not with whole numbers.

Ian Maurer
Ian Maurer
Numerade Educator