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College Algebra Essentials

Julie Miller

Chapter 0

Review of Prerequisites - all with Video Answers

Educators


Section 1

Sets and the Real Number Line

00:41

Problem 1

A _____ is a collection of items called elements.

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00:29

Problem 2

$\mathbb{W}=\{0,1,2,3, \ldots\}$ is called the set of _____ numbers.

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00:28

Problem 3

$\mathbb{N}=\{1,2,3, \ldots\}$ is called the set of _____ numbers.

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00:42

Problem 4

$\mathbb{Z}=\{\ldots,-3,-2,-1,0,1,2,3, \ldots\}$ is called the set of _____.

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00:52

Problem 5

A set can be defined using _____ - _____ notation by using a description of the set.

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00:38

Problem 6

Listing elements in a set within set braces is called the _____ method to define a set.

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01:16

Problem 7

Real numbers that can be expressed as a ratio of two integers are called _____ numbers.

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01:26

Problem 8

An _____ number is a real number that cannot be expressed as a ratio of two integers.

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01:44

Problem 9

The statement $x<y$ means that $x$ lies to the _____ of $y$ on the number line.

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01:17

Problem 10

The _____ _____ of $x$ is denoted by $|x|$.

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01:04

Problem 11

Write an absolute value expression to represent the distance between $a$ and $b$ on the number line: _____.

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01:22

Problem 12

Given the expression $b^{n},$ the value of $b$ is called the _____ and $n$ is called the _____ .

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01:25

Problem 13

The symbol $\sqrt{x}$ represents the principal _____ $\operatorname{root}$ of $x$.

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00:47

Problem 14

The expression $\frac{0}{5}$ equals _____, whereas $\frac{5}{0}$ is _____ _____.

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01:16

Problem 15

Write an English sentence to represent the algebraic statement.
$$3 \in \mathbb{N}$$

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01:33

Problem 16

Write an English sentence to represent the algebraic statement.
$$\frac{2}{5} \in \mathbb{Q}$$

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01:26

Problem 17

Write an English sentence to represent the algebraic statement.
$$-3.1 \notin \mathbb{Z}$$

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01:01

Problem 18

Write an English sentence to represent the algebraic statement.
$$\pi \notin \mathbb{Q}$$

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01:14

Problem 19

Write an English sentence to represent the algebraic statement.
$$\mathbb{Z} \subset \mathbb{R}$$

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00:53

Problem 20

Write an English sentence to represent the algebraic statement.
$$\mathbb{Q} \subset \mathbb{R}$$

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01:56

Problem 21

Determine whether the statement is true or false.
a. $-5 \in \mathbb{N}$
b. $-5 \in \mathbb{W}$
c. $-5 \in \mathbb{Z}$
d. $-5 \in \mathbb{Q}$

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01:15

Problem 22

Determine whether the statement is true or false.
a. $\frac{1}{3} \in \mathbb{N}$
b. $\frac{1}{3} \in \mathbb{W}$
c. $\frac{1}{3} \in \mathbb{Z}$
d. $\frac{1}{3} \in \mathbb{Q}$

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00:44

Problem 23

Determine whether the statement is true or false.
a. $0 . \overline{25} \in \mathbb{N}$
b. $0 . \overline{25} \in \mathbb{W}$
c. $0 . \overline{25} \in \mathbb{Z}$
d. $0 . \overline{25} \in \mathbb{Q}$

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01:10

Problem 24

Determine whether the statement is true or false.
a. $\pi \in \mathbb{Z}$
b. $\pi \in \mathbb{Q}$
c. $\pi \in \mathbb{H}$
d. $\pi \in \mathbb{R}$

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00:34

Problem 25

Determine whether the statement is true or false.
$25 \in\{x \mid x$ is an integer and a multiple of 5$\}$

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00:40

Problem 26

Determine whether the statement is true or false.
$-7 \in\{x \mid x$ is a natural number less than 10$\}$

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01:52

Problem 27

Determine whether the statement is true or false.
$-0 . \overline{8} \in\{x \mid x$ is a rational number greater than -0.8$\}$

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01:10

Problem 28

Determine whether the statement is true or false.
$0.45 \in\{x \mid x$ is a rational number less than $0 . \overline{45}\}$

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00:41

Problem 29

Determine whether the statement is true or false.
$22 \in\{x \mid x$ is an even whole number $\}$

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00:40

Problem 30

Determine whether the statement is true or false.
$-24 \in\{x \mid x$ is an integer and a multiple of 4$\}$

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00:26

Problem 31

Determine whether the statement is true or false.
A number can be both a rational number and an irrational number.

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00:44

Problem 32

Determine whether the statement is true or false.
A number can be both an integer and a rational number.

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01:14

Problem 33

Determine whether the statement is true or false.
a. $\{-2,-4,-6\}\subset\{-6,-4,-2,0\}$
b. $\{-6,-4,-2,0\}\subset\{-2,-4,-6\}$

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01:02

Problem 34

Determine whether the statement is true or false.
a. $\{\mathrm{FL}, \mathrm{GA}\} \subset\{\mathrm{FL}, \mathrm{NM}, \mathrm{GA}, \mathrm{TX}\}$
b. $\{\mathrm{FL}, \mathrm{NM}, \mathrm{GA}, \mathrm{TX}\} \subset\{\mathrm{FL}, \mathrm{GA}\}$

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01:02

Problem 35

Determine whether the statement is true or false.
a. $\mathbb{Z} \subset \mathbb{W}$
b. $\mathbb{W} \subset \mathbb{Z}$

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00:53

Problem 36

Determine whether the statement is true or false.
a. $\mathbb{Z} \subset \mathbb{Q}$
b. $\mathbb{Q} \subset \mathbb{Z}$

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00:51

Problem 37

Determine whether the statement is true or false.
a. $\mathbb{Q} \subset \mathbb{H}$
b. $\mathbb{H} \subset \mathbb{Q}$

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00:58

Problem 38

Determine whether the statement is true or false.
a. $\mathbb{H} \subset \mathbb{R}$
b. $\mathbb{Q} \subset \mathbb{R}$

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03:03

Problem 39

Refer to $A=\left\{\sqrt{5}, 0 . \overline{3}, 0.33,-0.9,-12, \frac{11}{4}, 6, \frac{\pi}{6}\right\}$
Determine which elements belong to the given set. (See Example 2)
a. $\mathbb{N}$
b. $\mathbb{W}$
c. $\mathbb{Z}$
d. $\mathbb{Q}$
e. $\mathbb{H}$
f. $\mathbb{R}$

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02:06

Problem 40

Refer to $B=\left\{\frac{\pi}{2}, 0,-4,0 . \overline{48}, 1,-\sqrt{13}, 9.4\right\} .$ Determine
which elements belong to the given set.
a. $\mathbb{N}$
b. $\mathbb{W}$
c. $\mathbb{Z}$
d. $\mathbb{Q}$
e. $\mathbb{H}$
f. $\mathbb{R}$

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00:41

Problem 41

Write each statement as an inequality.
$a$ is at least $5 .$

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00:39

Problem 42

Write each statement as an inequality.
$b$ is at most -6.

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00:28

Problem 43

Write each statement as an inequality.
$3 c$ is no more than $9 .$

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01:09

Problem 44

Write each statement as an inequality.
$8 d$ is no less than 16.

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00:48

Problem 45

Write each statement as an inequality.
The quantity $(m+4)$ exceeds 70 .

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00:35

Problem 46

Write each statement as an inequality.
The quantity $(n-7)$ is approximately equal to 4 .

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00:50

Problem 47

Determine whether the statement is true or false.
$$3.14<\pi$$

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01:24

Problem 48

Determine whether the statement is true or false.
$$-7<-\sqrt{7}$$

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00:49

Problem 49

Determine whether the statement is true or false.
$$6.7 \geq 6.7$$

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00:44

Problem 50

Determine whether the statement is true or false.
$$-2.1 \leq-2.1$$

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01:08

Problem 51

Determine whether the statement is true or false.
$$6 . \overline{15}>6.1 \overline{5}$$

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01:00

Problem 52

Determine whether the statement is true or false.
$$2.9 \overline{3}>2 . \overline{93}$$

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02:22

Problem 53

Determine whether the statement is true or false.
$$-\frac{9}{7}<-\frac{11}{8}$$

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01:20

Problem 54

Determine whether the statement is true or false.
$$-\frac{5}{3}<-\frac{9}{5}$$

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01:13

Problem 55

Write the interval notation and set-builder notation for each given graph. (See Example 3$)$

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00:54

Problem 56

Write the interval notation and set-builder notation for each given graph. (See Example 3$)$

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01:15

Problem 57

Write the interval notation and set-builder notation for each given graph. (See Example 3$)$

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01:03

Problem 58

Write the interval notation and set-builder notation for each given graph. (See Example 3$)$

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01:19

Problem 59

Write the interval notation and set-builder notation for each given graph. (See Example 3$)$

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01:16

Problem 60

Write the interval notation and set-builder notation for each given graph. (See Example 3$)$

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01:38

Problem 61

Graph the given set and write the corresponding interval notation. (See Example 3$)$
$$\{x \mid x \leq 6\}$$

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01:26

Problem 62

Graph the given set and write the corresponding interval notation. (See Example 3$)$
$$\{x \mid x<-4\}$$

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01:57

Problem 63

Graph the given set and write the corresponding interval notation. (See Example 3$)$
$$\left\{x \mid-\frac{7}{6}<x \leq \frac{1}{3}\right\}$$

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00:58

Problem 64

Graph the given set and write the corresponding interval notation. (See Example 3$)$
$$\left\{x \mid-\frac{4}{3} \leq x<\frac{7}{4}\right\}$$

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01:27

Problem 65

Graph the given set and write the corresponding interval notation. (See Example 3$)$
$$\{x \mid 4<x\}$$

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01:10

Problem 66

Graph the given set and write the corresponding interval notation. (See Example 3$)$
$$\{x \mid-3 \leq x\}$$

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01:36

Problem 67

Interval notation is given for several sets of real numbers. Graph the set and write the corresponding set-builder notation. (See Example 3$)$
$$(-3,7]$$

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01:12

Problem 68

Interval notation is given for several sets of real numbers. Graph the set and write the corresponding set-builder notation. (See Example 3$)$
$$[-4,-1)$$

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01:29

Problem 69

Interval notation is given for several sets of real numbers. Graph the set and write the corresponding set-builder notation. (See Example 3$)$
$$(-\infty, 6.7]$$

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01:18

Problem 70

Interval notation is given for several sets of real numbers. Graph the set and write the corresponding set-builder notation. (See Example 3$)$
$$(-\infty,-3.2)$$

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01:27

Problem 71

Interval notation is given for several sets of real numbers. Graph the set and write the corresponding set-builder notation. (See Example 3$)$
$$\left[-\frac{3}{5}, \infty\right)$$

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00:58

Problem 72

Interval notation is given for several sets of real numbers. Graph the set and write the corresponding set-builder notation. (See Example 3$)$
$$\left(\frac{7}{8}, \infty\right)$$

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01:50

Problem 73

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
$$|-6|$$

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00:38

Problem 74

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
$$|-4|$$

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00:28

Problem 75

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
$$|0|$$

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00:43

Problem 76

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
$$|1|$$

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01:32

Problem 77

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
$$|\sqrt{2}-2|$$

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01:03

Problem 78

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
$$|\sqrt{6}-6|$$

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01:32

Problem 79

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
a. $|\pi-3|$
b. $|3-\pi|$

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02:07

Problem 80

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
a. $|m-11|$ for $m \geq 11$
b. $|m-11|$ for $m<11$

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01:32

Problem 81

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
a. $|x+2|$ for $x \geq-2$
b. $|x+2|$ for $x<-2$

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01:26

Problem 82

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
a. $|t+6|$ for $t<-6$
b. $|t+6|$ for $t \geq-6$

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01:57

Problem 83

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
a. $\frac{|z-5|}{z-5}$ for $z>5$
b. $\frac{|z-5|}{z-5}$ for $z<5$

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01:50

Problem 84

Simplify each expression by writing the expression without absolute value bars. (See Examples 4-5)
a. $\frac{7-x}{|7-x|}$ for $x<7$
b. $\frac{7-x}{|7-x|}$ for $x>7$

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01:12

Problem 85

Write an absolute value expression to represent the distance between the two points on the number line. Then simplify without absolute value bars. (See Example 6 )
$$1 \text { and } 6$$

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01:05

Problem 86

Write an absolute value expression to represent the distance between the two points on the number line. Then simplify without absolute value bars. (See Example 6 )
$$2 \text { and } 9$$

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01:39

Problem 87

Write an absolute value expression to represent the distance between the two points on the number line. Then simplify without absolute value bars. (See Example 6 )
$$3 \text { and }-4$$

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01:38

Problem 88

Write an absolute value expression to represent the distance between the two points on the number line. Then simplify without absolute value bars. (See Example 6 )
$$-8 \text { and } 2$$

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02:18

Problem 89

Write an absolute value expression to represent the distance between the two points on the number line. Then simplify without absolute value bars. (See Example 6 )
$$8 \text { and } \sqrt{3}$$

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02:21

Problem 90

Write an absolute value expression to represent the distance between the two points on the number line. Then simplify without absolute value bars. (See Example 6 )
$$11 \text { and } \sqrt{5}$$

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01:55

Problem 91

Write an absolute value expression to represent the distance between the two points on the number line. Then simplify without absolute value bars. (See Example 6 )
$$6 \text { and } 2 \pi$$

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01:40

Problem 92

Write an absolute value expression to represent the distance between the two points on the number line. Then simplify without absolute value bars. (See Example 6 )
$$3 \text { and } \pi$$

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02:29

Problem 93

Simplify the expression. (See Examples 7-8)
a. $4^{2}$
b. $(-4)^{2}$
c. $-4^{2}$
d. $\sqrt{4}$
e. $-\sqrt{4}$
f. $\sqrt{-4}$

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01:41

Problem 94

Simplify the expression. (See Examples 7-8)
a. $9^{2}$
b. $(-9)^{2}$
c. $-9^{2}$
d. $\sqrt{9}$
e. $-\sqrt{9}$
f. $\sqrt{-9}$

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02:02

Problem 95

Simplify the expression. (See Examples 7-8)
a. $\sqrt[3]{8}$
b. $\sqrt[3]{-8}$
c. $-\sqrt[3]{8}$
d. $\sqrt{100}$
e. $\sqrt{-100}$
f. $-\sqrt{100}$

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01:33

Problem 96

Simplify the expression. (See Examples 7-8)
a. $\sqrt[3]{27}$
b. $\sqrt[3]{-27}$
c. $-\sqrt[3]{27}$
d. $\sqrt{49}$
e. $\sqrt{-49}$
f. $-\sqrt{49}$

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00:53

Problem 97

Simplify the expression. (See Examples 7-8)
$$\left(\frac{2}{3}\right)^{3}$$

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00:56

Problem 98

Simplify the expression. (See Examples 7-8)
$$\left(\frac{4}{5}\right)^{3}$$

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01:15

Problem 99

Simplify the expression. (See Examples 7-8)
$$(-0.2)^{4}$$

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00:47

Problem 100

Simplify the expression. (See Examples 7-8)
$$(-0.1)^{4}$$

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01:00

Problem 101

Simplify the expression. (See Examples 7-8)
$$\sqrt{\frac{169}{25}}$$

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00:53

Problem 102

Simplify the expression. (See Examples 7-8)
$$\sqrt{\frac{121}{36}}$$

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02:52

Problem 103

Simplify the expression. (See Examples 9-11)
$$20-12\left(36 \div 3^{2} \div 2\right)$$

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02:26

Problem 104

Simplify the expression. (See Examples 9-11)
$$200-2^{2}\left(6 \div \frac{1}{2} \cdot 4\right)$$

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03:13

Problem 105

Simplify the expression. (See Examples 9-11)
$$6-\left\{-12+3\left[(1-6)^{2}-18\right]\right\}$$

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02:56

Problem 106

Simplify the expression. (See Examples 9-11)
$$-5-\left\{4-6\left[(2-8)^{2}-31\right]\right\}$$

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00:47

Problem 107

Simplify the expression. (See Examples 9-11)
$$\sqrt{5^{2}-3^{2}}$$

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00:45

Problem 108

Simplify the expression. (See Examples 9-11)
$$\sqrt{6^{2}+8^{2}}$$

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00:42

Problem 109

Simplify the expression. (See Examples 9-11)
$$(\sqrt{9}+\sqrt{16})^{2}$$

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00:49

Problem 110

Simplify the expression. (See Examples 9-11)
$$(\sqrt[3]{8}+\sqrt[3]{125})^{3}$$

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01:59

Problem 111

Simplify the expression. (See Examples 9-11)
$$-4 \cdot\left(\frac{2}{5}-\frac{7}{10}\right)^{2}$$

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02:16

Problem 112

Simplify the expression. (See Examples 9-11)
$$6 \cdot\left[\left(\frac{1}{3}\right)^{2}-\left(\frac{1}{2}\right)^{2}\right]$$

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02:57

Problem 113

Simplify the expression. (See Examples 9-11)
$$9-(6+|| 3-7|-8|) \div \sqrt{25}$$

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02:36

Problem 114

Simplify the expression. (See Examples 9-11)
$$8-2(4+\| 2-5|-5|) \div \sqrt{9}$$

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03:12

Problem 115

Simplify the expression. (See Examples 9-11)
$$\frac{|11-13|-4 \cdot 2}{\sqrt{12^{2}+5^{2}}-3-10}$$

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02:30

Problem 116

Simplify the expression. (See Examples 9-11)
$$\frac{(4-9)^{2}+2^{2}-3^{2}}{|-7+4|+(-12) \div 4}$$

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02:48

Problem 117

Use the formula $W_{h}=W_{s}\left(\frac{4000}{4000+h}\right)^{2}$ to compute the weight of an object $W_{h}$ (in lb) at a height of $h$ mi above sea level. The value of $W_{s}$ is the weight of the object (in lb) at sea level.
If a man weighs $200 \mathrm{lb}$ at sea level, evaluate $W_{h}=(200)\left(\frac{4000}{4000+5.5}\right)^{2}$ to determine his weight at the top of Mt. Everest. (Mt. Everest is $29,029 \mathrm{ft}$ above sea level, or approximately $5.5 \mathrm{mi}$.) Round to 1 decimal place.

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01:43

Problem 118

Use the formula $W_{h}=W_{s}\left(\frac{4000}{4000+h}\right)^{2}$ to compute the weight of an object $W_{h}$ (in lb) at a height of $h$ mi above sea level. The value of $W_{s}$ is the weight of the object (in lb) at sea level.
In $1976,$ an SR- 71 Blackbird aircraft broke the world record for altitude by an airplane (not a rocket) by reaching an altitude of $85,135 \mathrm{ft}$ (approximately $16.1 \mathrm{mi}$ ). (Source: Lockheed Martin, www.lockheedmartin.com) If the pilot weighs $175 \mathrm{lb}$ at sea level, use the formula $W_{h}=(175)\left(\frac{4000}{4000+16.1}\right)^{2}$ to determine his weight at an altitude of $16.1 \mathrm{mi} .$ Round to 1 decimal place.

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Destin Priester
Numerade Educator
01:45

Problem 119

Cone-shaped paper cups are used at the water cooler in many exercise facilities. Using the formula for the volume of a cone, the volume in cubic centimeters $(\mathrm{cc})$ of this cup is $V=\frac{\pi(3.8)^{2} \cdot 8}{3}$. Approximate the volume to the nearest cubic centimeter.

Destin Priester
Destin Priester
Numerade Educator
01:32

Problem 120

An inflated balloon has a volume of $6.0 \mathrm{~L}$ (liters) at sea level, where the pressure is $1.0 \mathrm{~atm}$ (atmosphere). The balloon is allowed to ascend until the pressure is 0.5 atm. During the ascent, the temperature of the gas in the balloon falls from $20^{\circ} \mathrm{C}$ to $-23^{\circ} \mathrm{C}$. Using the ideal-gas equation from chemistry, the new volume (in liters) of the gas in the balloon is $V=6.0\left(\frac{1.0}{0.5}\right)\left(\frac{250}{293}\right)$. Approximate this volume to the nearest tenth of a liter.

Destin Priester
Destin Priester
Numerade Educator
02:43

Problem 121

Explain why all terminating decimal numbers are rational numbers.

Jill Tolbert
Jill Tolbert
Numerade Educator
01:11

Problem 122

Explain why all integers are rational numbers.

Jill Tolbert
Jill Tolbert
Numerade Educator
02:53

Problem 123

When is a parenthesis used when writing interval notation?

Destin Priester
Destin Priester
Numerade Educator
02:19

Problem 124

When is a bracket used when writing interval notation?

Destin Priester
Destin Priester
Numerade Educator
01:44

Problem 125

Explain why $\mathbb{Z} \subset \mathbb{Q}$ but $\mathbb{Q} \not \subset \mathbb{Z}$.

Yujie Wang
Yujie Wang
College of San Mateo
01:19

Problem 126

Explain why the statement \{1\}$\subset \mathbb{Z}$ is a valid statement, but $1 \subset \mathbb{Z}$ does not make sense.

Yujie Wang
Yujie Wang
College of San Mateo
00:53

Problem 127

If $n>0,$ then $n-|n|=$ _____.

Destin Priester
Destin Priester
Numerade Educator
02:08

Problem 128

If $n<0,$ then $n-|n|=$_____.

Destin Priester
Destin Priester
Numerade Educator
01:06

Problem 129

If $n>0,$ then $n+|n|=$ _____ .

Destin Priester
Destin Priester
Numerade Educator
00:51

Problem 130

If $n<0,$ then $n+|n|=$ _____ .

Destin Priester
Destin Priester
Numerade Educator
00:40

Problem 131

If $n>0,$ then $-|n|=$ _____ .

Destin Priester
Destin Priester
Numerade Educator
01:02

Problem 132

If $n<0,$ then $-|n|=$ _____.

Destin Priester
Destin Priester
Numerade Educator
01:11

Problem 133

Write an inequality representing the given statement.
$b$ is positive.

Destin Priester
Destin Priester
Numerade Educator
00:55

Problem 134

Write an inequality representing the given statement.
$a$ is negative.

Destin Priester
Destin Priester
Numerade Educator
01:00

Problem 135

Write an inequality representing the given statement.
$b$ is nonnegative.

Destin Priester
Destin Priester
Numerade Educator
00:53

Problem 136

Write an inequality representing the given statement.
$a$ is not positive.

Destin Priester
Destin Priester
Numerade Educator
01:48

Problem 137

Determine the sign of the expression. Assume that $a, b,$ and $c$ are real numbers and $a<0, b>0,$ and $c<0$.
$$\frac{a b^{2}}{c^{3}}$$

Destin Priester
Destin Priester
Numerade Educator
01:28

Problem 138

Determine the sign of the expression. Assume that $a, b,$ and $c$ are real numbers and $a<0, b>0,$ and $c<0$.
$$\frac{a^{2} c}{b^{4}}$$

Destin Priester
Destin Priester
Numerade Educator
02:01

Problem 139

Determine the sign of the expression. Assume that $a, b,$ and $c$ are real numbers and $a<0, b>0,$ and $c<0$.
$$\frac{b(a+c)^{3}}{a^{2}}$$

Destin Priester
Destin Priester
Numerade Educator
01:10

Problem 140

Determine the sign of the expression. Assume that $a, b,$ and $c$ are real numbers and $a<0, b>0,$ and $c<0$.
$$\frac{(a+b)^{2}(b+c)^{4}}{b}$$

Destin Priester
Destin Priester
Numerade Educator
01:49

Problem 141

Use a calculator to approximate the expression to 2 decimal places.
$$5000\left(1+\frac{0.06}{12}\right)^{(12)(5)}$$

Destin Priester
Destin Priester
Numerade Educator
01:28

Problem 142

Use a calculator to approximate the expression to 2 decimal places.
$$8500\left(1+\frac{0.05}{4}\right)^{(4)(30)}$$

Destin Priester
Destin Priester
Numerade Educator
01:08

Problem 143

Use a calculator to approximate the expression to 2 decimal places.
$$\frac{-3+5 \sqrt{2}}{7}$$

Destin Priester
Destin Priester
Numerade Educator
01:32

Problem 144

Use a calculator to approximate the expression to 2 decimal places.
$$\frac{6-3 \sqrt{5}}{4}$$

Destin Priester
Destin Priester
Numerade Educator
04:27

Problem 145

To evaluate the expression $\frac{-3+\sqrt{3^{2}-4(-5)(2)}}{2(-5)}$ a student entered this expression on a calculator as shown. Find the error made by the student, and correct the mistake.

Jill Tolbert
Jill Tolbert
Numerade Educator