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Algebra and Trigonometry

Robert Blitzer

Chapter 1

Equations and Inequalities - all with Video Answers

Educators


Section 1

Graphs and Graphing Utilities

00:45

Problem 1

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$(1,4)$$

Mary Brese
Mary Brese
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00:43

Problem 2

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$(2,5)$$

Mary Brese
Mary Brese
Numerade Educator
00:38

Problem 3

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$(-2,3)$$

Mary Brese
Mary Brese
Numerade Educator
00:38

Problem 4

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$(-1,4)$$

Mary Brese
Mary Brese
Numerade Educator
00:44

Problem 5

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$(-3,-5)$$

Mary Brese
Mary Brese
Numerade Educator
00:35

Problem 6

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$(-4,-2)$$

Mary Brese
Mary Brese
Numerade Educator
00:40

Problem 7

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$
(4,-1)
$$

Mary Brese
Mary Brese
Numerade Educator
00:43

Problem 8

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$
(3,-2)
$$

Mary Brese
Mary Brese
Numerade Educator
00:48

Problem 9

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$
(-4,0)
$$

Mary Brese
Mary Brese
Numerade Educator
00:49

Problem 10

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$
(0,-3)
$$

Mary Brese
Mary Brese
Numerade Educator
01:29

Problem 11

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$
\left(\frac{7}{2},-\frac{3}{2}\right)
$$

Mary Brese
Mary Brese
Numerade Educator
01:37

Problem 12

In Exercises 1–12, plot the given point in a rectangular coordinate system.
$$
\left(-\frac{5}{2}, \frac{3}{2}\right)
$$

Mary Brese
Mary Brese
Numerade Educator
04:31

Problem 13

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$y=x^{2}-2$$

Mary Brese
Mary Brese
Numerade Educator
05:22

Problem 14

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$y=x^{2}+2$$

Mary Brese
Mary Brese
Numerade Educator
04:27

Problem 15

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$y=x-2$$

Mary Brese
Mary Brese
Numerade Educator
04:37

Problem 16

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=x+2
$$

Mary Brese
Mary Brese
Numerade Educator
04:46

Problem 17

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=2 x+1
$$

Mary Brese
Mary Brese
Numerade Educator
05:13

Problem 18

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=2 x-4
$$

Mary Brese
Mary Brese
Numerade Educator
04:55

Problem 19

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=-\frac{1}{2} x
$$

Mary Brese
Mary Brese
Numerade Educator
04:16

Problem 20

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=-\frac{1}{2} x+2
$$

Mary Brese
Mary Brese
Numerade Educator
02:42

Problem 21

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=2|x|
$$

Mary Brese
Mary Brese
Numerade Educator
02:32

Problem 22

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=-2|x|
$$

Mary Brese
Mary Brese
Numerade Educator
02:39

Problem 23

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=|x|+1
$$

Mary Brese
Mary Brese
Numerade Educator
02:40

Problem 24

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=|x|-1
$$

Mary Brese
Mary Brese
Numerade Educator
04:05

Problem 25

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=9-x^{2}
$$

Mary Brese
Mary Brese
Numerade Educator
03:38

Problem 26

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=-x^{2}
$$

Mary Brese
Mary Brese
Numerade Educator
04:10

Problem 27

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=x^{3}
$$

Mary Brese
Mary Brese
Numerade Educator
04:26

Problem 28

Graph each equation in Exercises $13-28 .$ Let $x=-3,-2,-1,0$ $1,2,$ and 3.
$$
y=x^{3}-1
$$

Mary Brese
Mary Brese
Numerade Educator
02:11

Problem 29

In Exercises 29–32, match the viewing rectangle with the correct figure. Then label the tick marks in the figure to illustrate this viewing rectangle.
$$
[-5,5,1] \text { by }[-5,5,1]
$$
A. (GRAPH NOT COPY)
B. (GRAPH NOT COPY)
C. (GRAPH NOT COPY)

Mary Brese
Mary Brese
Numerade Educator
02:05

Problem 30

In Exercises 29–32, match the viewing rectangle with the correct figure. Then label the tick marks in the figure to illustrate this viewing rectangle.
$$
[-10,10,2] \text { by }[-4,4,2]
$$
A. (GRAPH NOT COPY)
B. (GRAPH NOT COPY)
C. (GRAPH NOT COPY)

Mary Brese
Mary Brese
Numerade Educator
02:15

Problem 31

In Exercises 29–32, match the viewing rectangle with the correct figure. Then label the tick marks in the figure to illustrate this viewing rectangle.
$$
[-20,80,10] \text { by }[-30,70,10]
$$
A. (GRAPH NOT COPY)
B. (GRAPH NOT COPY)
C. (GRAPH NOT COPY)

Mukesh Devi
Mukesh Devi
Numerade Educator
02:41

Problem 32

In Exercises 29–32, match the viewing rectangle with the correct figure. Then label the tick marks in the figure to illustrate this viewing rectangle.
$$
[-40,40,20] \text { by }[-1000,1000,100]
$$
A. (GRAPH NOT COPY)
B. (GRAPH NOT COPY)
C. (GRAPH NOT COPY)

Mary Brese
Mary Brese
Numerade Educator
02:50

Problem 33

The table of values was generated by a graphing utility with a TABLE feature. Use the table to solve Exercises 33–40.
Which equation corresponds to $Y_{2}$ in the table?
A. $y_{2}=x+8$
B. $y_{2}=x-2$
C. $y_{2}=2-x$
D. $y_{2}=1-2 x$

Mary Brese
Mary Brese
Numerade Educator
03:30

Problem 34

The table of values was generated by a graphing utility with a TABLE feature. Use the table to solve Exercises 33–40.
Which equation corresponds to $Y_{1}$ in the table?
A. $y_{1}=-3 x$
B. $y_{1}=x^{2}$
C. $y_{1}=-x^{2}$
D. $y_{1}=2-x$

Mary Brese
Mary Brese
Numerade Educator
01:48

Problem 35

The table of values was generated by a graphing utility with a TABLE feature. Use the table to solve Exercises 33–40.
Does the graph of $\mathrm{Y}_{2}$ pass through the origin?

Mary Brese
Mary Brese
Numerade Educator
01:48

Problem 36

The table of values was generated by a graphing utility with a TABLE feature. Use the table to solve Exercises 33–40.
Does the graph of $Y_{1}$ pass through the origin?

Mary Brese
Mary Brese
Numerade Educator
01:21

Problem 37

The table of values was generated by a graphing utility with a TABLE feature. Use the table to solve Exercises 33–40.
At which point does the graph of $Y_{2}$ cross the $x$ -axis?

Mary Brese
Mary Brese
Numerade Educator
01:22

Problem 38

The table of values was generated by a graphing utility with a TABLE feature. Use the table to solve Exercises 33–40.
At which point does the graph of $Y_{2}$ cross the $y$ -axis?

Mary Brese
Mary Brese
Numerade Educator
01:52

Problem 39

The table of values was generated by a graphing utility with a TABLE feature. Use the table to solve Exercises 33–40.
At which points do the graphs of $Y_{1}$ and $Y_{2}$ intersect?

Mary Brese
Mary Brese
Numerade Educator
01:38

Problem 40

The table of values was generated by a graphing utility with a TABLE feature. Use the table to solve Exercises 33–40.
For which values of $x$ is $Y_{1}=Y_{2} ?$

Mary Brese
Mary Brese
Numerade Educator
01:07

Problem 41

In Exercises $41-46,$ use the graph to a. determine the
$x$ -intercepts, if any; b. determine the $y$ -intercepts, if any. For each graph, tick marks along the axes represent one unit each.

Mary Brese
Mary Brese
Numerade Educator
00:56

Problem 42

In Exercises $41-46,$ use the graph to a. determine the
$x$ -intercepts, if any; b. determine the $y$ -intercepts, if any. For each graph, tick marks along the axes represent one unit each.

Mary Brese
Mary Brese
Numerade Educator
01:25

Problem 43

In Exercises $41-46,$ use the graph to a. determine the
$x$ -intercepts, if any; b. determine the $y$ -intercepts, if any. For each graph, tick marks along the axes represent one unit each.

Mary Brese
Mary Brese
Numerade Educator
01:20

Problem 44

In Exercises $41-46,$ use the graph to a. determine the
$x$ -intercepts, if any; b. determine the $y$ -intercepts, if any. For each graph, tick marks along the axes represent one unit each.

Mary Brese
Mary Brese
Numerade Educator
00:45

Problem 45

In Exercises $41-46,$ use the graph to a. determine the
$x$ -intercepts, if any; b. determine the $y$ -intercepts, if any. For each graph, tick marks along the axes represent one unit each.

Mary Brese
Mary Brese
Numerade Educator
00:45

Problem 46

In Exercises $41-46,$ use the graph to a. determine the
$x$ -intercepts, if any; b. determine the $y$ -intercepts, if any. For each graph, tick marks along the axes represent one unit each.

Mary Brese
Mary Brese
Numerade Educator
03:02

Problem 47

Write each English sentence as an equation in two variables. Then graph the equation.
The $y$ -value is four more than twice the $x$ -value.

Mary Brese
Mary Brese
Numerade Educator
03:44

Problem 48

write each English sentence as an equation in two variables. Then graph the equation.
The $y$ -value is the difference between four and twice the $x$ -value.

Mary Brese
Mary Brese
Numerade Educator
04:22

Problem 49

write each English sentence as an equation in two variables. Then graph the equation.
The $y$ -value is three decreased by the square of the $x$ -value.

Mary Brese
Mary Brese
Numerade Educator
04:24

Problem 50

write each English sentence as an equation in two variables. Then graph the equation.
The $y$ -value is two more than the square of the $x$ -value.

Mary Brese
Mary Brese
Numerade Educator
01:54

Problem 51

Graph each equation.
$y=5(\text { Let } x=-3,-2,-1,0,1,2, \text { and } 3 .)$

Mary Brese
Mary Brese
Numerade Educator
02:09

Problem 52

Graph each equation.
$y=-1 \text { (Let } x=-3,-2,-1,0,1,2, \text { and } 3 .)$

Mary Brese
Mary Brese
Numerade Educator
04:40

Problem 53

Graph each equation.
$y=\frac{1}{x}\left(\text { Let } x=-2,-1,-\frac{1}{2},-\frac{1}{3}, \frac{1}{3}, \frac{1}{2}, 1, \text { and } 2 .\right)$

Mary Brese
Mary Brese
Numerade Educator
04:38

Problem 54

Graph each equation.
$y=-\frac{1}{x}\left(\text { Let } x=-2,-1,-\frac{1}{2},-\frac{1}{3}, \frac{1}{3}, \frac{1}{2}, 1, \text { and } 2 .\right)$

Mary Brese
Mary Brese
Numerade Educator
05:25

Problem 55

Use this information to solve Exercises.
A. Use the appropriate line graph to estimate the percentage of seniors who used marijuana in 2010.
B. Use the appropriate formula to determine the percentage of seniors who used marijuana in $2010 .$ How does this compare with your estimate in part (a)?
C. Use the appropriate line graph to estimate the percentage of seniors who used alcohol in 2010.
D. Use the appropriate formula to determine the percentage of seniors who used alcohol in $2010 .$ How does this compare with your estimate in part (c)?
E. For the period from 1990 through $2014,$ in which year was marijuana use by seniors at a maximum? Estimate the percentage of seniors who used marijuana in that year.

Mary Brese
Mary Brese
Numerade Educator
04:40

Problem 56

Use this information to solve Exercises $55-56$.
A. Use the appropriate line graph to estimate the percentage of seniors who used alcohol in 2014.
B. Use the appropriate formula to determine the percentage of seniors who used alcohol in $2014 .$ How does this compare with your estimate in part (a)?
C. Use the appropriate line graph to estimate the percentage of seniors who used marijuana in 2014.
D. Use the appropriate formula to determine the percentage of seniors who used marijuana in $2014 .$ How does this compare with your estimate in part (c)?
E. For the period from 1990 through $2014,$ in which year was alcohol use by seniors at a maximum? What percentage of seniors used alcohol in that year.

Mary Brese
Mary Brese
Numerade Educator
01:48

Problem 57

Contrary to popular belief, older people do not need less sleep than younger adults. However, the line graphs show that they awaken more often during the night. The numerous awakenings are one reason why some elderly individuals report that sleep is less restful than it had been in the past. Use the line graphs to solve Exercises $57-60$.
At which age, estimated to the nearest year, do women have the least number of awakenings during the night? What is the average number of awakenings at that age?

Mary Brese
Mary Brese
Numerade Educator
02:01

Problem 58

Contrary to popular belief, older people do not need less sleep than younger adults. However, the line graphs show that they awaken more often during the night. The numerous awakenings are one reason why some elderly individuals report that sleep is less restful than it had been in the past. Use the line graphs to solve Exercises $57-60$.
At which age do men have the greatest number of awakenings during the night? What is the average number of awakenings at that age?

Mary Brese
Mary Brese
Numerade Educator
02:03

Problem 59

Contrary to popular belief, older people do not need less sleep than younger adults. However, the line graphs show that they awaken more often during the night. The numerous awakenings are one reason why some elderly individuals report that sleep is less restful than it had been in the past. Use the line graphs to solve Exercises $57-60$.
Estimate, to the nearest tenth, the difference between the average number of awakenings during the night for $25-$ year-old men and 25 -year-old women.

Mary Brese
Mary Brese
Numerade Educator
01:42

Problem 60

Contrary to popular belief, older people do not need less sleep than younger adults. However, the line graphs show that they awaken more often during the night. The numerous awakenings are one reason why some elderly individuals report that sleep is less restful than it had been in the past. Use the line graphs to solve Exercises $57-60$.
Estimate, to the nearest tenth, the difference between the average number of awakenings during the night for 18 -year-old men and 18 -year-old women.

Mary Brese
Mary Brese
Numerade Educator
00:57

Problem 61

Explaining the Concepts
What is the rectangular coordinate system?

Mary Brese
Mary Brese
Numerade Educator
03:37

Problem 62

Explaining the Concepts
Explain how to plot a point in the rectangular coordinate system. Give an example with your explanation.

Mary Brese
Mary Brese
Numerade Educator
03:39

Problem 63

Explaining the Concepts
Explain why $(5,-2)$ and $(-2,5)$ do not represent the same point.

Mary Brese
Mary Brese
Numerade Educator
01:40

Problem 64

Explain how to graph an equation in the rectangular coordinate system.

Mary Brese
Mary Brese
Numerade Educator
02:17

Problem 65

Explaining the Concepts
What does a $[-20,2,1]$ by $[-4,5,0.5]$ viewing rectangle mean?

Mary Brese
Mary Brese
Numerade Educator
19:19

Problem 66

Technology Exercise
Use a graphing utility to verify each of your hand-drawn graphs in Exercises $13-28 .$ Experiment with the settings for the viewing rectangle to make the graph displayed by the graphing utility resemble your hand-drawn graph as much as possible.

Mary Brese
Mary Brese
Numerade Educator
00:47

Problem 67

determine whether each statement makes sense or does not make sense, and explain your reasoning.
The rectangular coordinate system provides a geometric picture of what an equation in two variables looks like.

Mary Brese
Mary Brese
Numerade Educator
00:52

Problem 68

Determine whether each statement makes sense or does not make sense, and explain your reasoning.
There is something wrong with my graphing utility because it is not displaying numbers along the $x$ - and $y$ -axes.

Mary Brese
Mary Brese
Numerade Educator
01:19

Problem 69

Determine whether each statement makes sense or does not make sense, and explain your reasoning.
I used the ordered pairs $(-2,2),(0,0),$ and $(2,2)$ to graph a straight line.

Mary Brese
Mary Brese
Numerade Educator
01:28

Problem 70

Determine whether each statement makes sense or does not make sense, and explain your reasoning.
I used the ordered pairs (time of day, calories that I burned)
to obtain a graph that is a horizontal line.

Mary Brese
Mary Brese
Numerade Educator
02:06

Problem 71

Determine whether each statement is true or false. If the statement is false, make the necessary change(s) to produce a true statement.
If the product of a point's coordinates is positive, the point must be in quadrant I.

Mary Brese
Mary Brese
Numerade Educator
01:12

Problem 72

Determine whether each statement is true or false. If the statement is false, make the necessary change(s) to produce a true statement.
If a point is on the $x$ -axis, it is neither up nor down, so $x=0$

Mary Brese
Mary Brese
Numerade Educator
01:34

Problem 73

Determine whether each statement is true or false. If the statement is false, make the necessary change(s) to produce a true statement.
If a point is on the $y$ -axis, its $x$ -coordinate must be $0 .$

Mary Brese
Mary Brese
Numerade Educator
01:53

Problem 74

Determine whether each statement is true or false. If the statement is false, make the necessary change(s) to produce a true statement.
The ordered pair $(2,5)$ satisfies $3 y-2 x=-4$.

Mary Brese
Mary Brese
Numerade Educator
02:41

Problem 75

List the quadrant or quadrants satisfying each condition.
$$x y>0$$

Mary Brese
Mary Brese
Numerade Educator
01:53

Problem 76

In Exercises $75-78,$ list the quadrant or quadrants satisfying each condition.
$$
\frac{y}{x}<0
$$

Mary Brese
Mary Brese
Numerade Educator
02:05

Problem 77

In Exercises $75-78,$ list the quadrant or quadrants satisfying each condition.
$x^{3}>0$ and $y^{3}<0$

Mary Brese
Mary Brese
Numerade Educator
02:19

Problem 78

In Exercises $75-78,$ list the quadrant or quadrants satisfying each condition.
$x^{3}<0$ and $y^{3}>0$

Mary Brese
Mary Brese
Numerade Educator
01:12

Problem 79

In Exercises $79-82,$ match the story with the correct figure. The figures are labeled $(a),(b),(c),$ and $(d)$
As the blizzard got worse, the snow fell harder and harder.

Mary Brese
Mary Brese
Numerade Educator
00:39

Problem 80

In Exercises $79-82,$ match the story with the correct figure. The figures are labeled $(a),(b),(c),$ and $(d)$.
The snow fell more and more softly.

Mary Brese
Mary Brese
Numerade Educator
01:09

Problem 81

In Exercises $79-82,$ match the story with the correct figure. The figures are labeled $(a),(b),(c),$ and $(d)$
It snowed hard, but then it stopped. After a short time, the snow started falling softly.

Mary Brese
Mary Brese
Numerade Educator
00:46

Problem 82

Match the story with the correct figure. The figures are labeled $(a),(b),(c),$ and $(d)$
It snowed softly, and then it stopped. After a short time, the snow started falling hard.

Mary Brese
Mary Brese
Numerade Educator
00:58

Problem 83

Select the graph that best illustrates each story.
An airplane flew from Miami to San Francisco.

Mary Brese
Mary Brese
Numerade Educator
00:50

Problem 84

Select the graph that best illustrates each story.
At noon, you begin to breathe in.

Mary Brese
Mary Brese
Numerade Educator
01:24

Problem 85

Select the graph that best illustrates each story.
Measurements are taken of a person's height from birth to age 100.

Mary Brese
Mary Brese
Numerade Educator
01:55

Problem 86

Equations and Inequalities
You begin your bike ride by riding down a hill. Then you ride up another hill. Finally, you ride along a level surface before coming to a stop.

Mary Brese
Mary Brese
Numerade Educator
01:39

Problem 87

Will help you prepare for the material covered in the next section.
If 6 is substituted for $x$ in the equation
$$
2(x-3)-17=13-3(x+2)
$$
is the resulting statement true or false?

Mary Brese
Mary Brese
Numerade Educator
01:21

Problem 88

Exercises $87-89$ will help you prepare for the material covered in the next section.
Multiply and simplify: $12\left(\frac{x+2}{4}-\frac{x-1}{3}\right)$

Mary Brese
Mary Brese
Numerade Educator
01:14

Problem 89

Exercises $87-89$ will help you prepare for the material covered in the next section.
Multiply and simplify: $(x-3)\left(\frac{3}{x-3}+9\right)$

Mary Brese
Mary Brese
Numerade Educator