• Home
  • Textbooks
  • Prealgebra
  • Functions and Graphing

Prealgebra

Carol E. Malloy, Rhonda J. Molix-Bailey, Jack Price

Chapter 7

Functions and Graphing - all with Video Answers

Educators


Section 1

Functions

00:40

Problem 1

Determine whether each relation is a function. Explain.
$$\{(13,5),(-4,12),(6,0),(13,10)\}$$

Brandon Fox
Brandon Fox
Numerade Educator
01:02

Problem 2

Determine whether each relation is a function. Explain.
$$\{(9.2,7),(9.4,11),(9.5,9.5),(9.8,8)\}$$

Brandon Fox
Brandon Fox
Numerade Educator
01:05

Problem 3

Determine whether each relation is a function. Explain.
$$\begin{array}{|c|c|}\hline \text { Domain } & \text { Range } \\\hline-3 & 3 \\\hline-1 & -2 \\\hline 0 & 5 \\\hline 1 & -4 \\
\hline 2 & 3 \\\hline\end{array}$$

Brandon Fox
Brandon Fox
Numerade Educator
00:40

Problem 4

Determine whether each relation is a function. Explain.
$$\begin{array}{|r|r|}\hline x & y \\\hline 5 & 4 \\\hline 2 & 8 \\\hline-7 & 9 \\\hline 2 & 12 \\\hline 5 & 14 \\\hline
\end{array}$$

Brandon Fox
Brandon Fox
Numerade Educator
02:13

Problem 5

Determine whether each relation is a function. Explain.
(GRAPH CANT COPY)

Brandon Fox
Brandon Fox
Numerade Educator
00:53

Problem 6

Determine whether each relation is a function. Explain.
(GRAPH CANT COPY)

Brandon Fox
Brandon Fox
Numerade Educator
01:15

Problem 7

Use the data in the table.
(GRAPH CANT COPY)
Do the data represent a function? Explain.

Brandon Fox
Brandon Fox
Numerade Educator
01:24

Problem 8

Use the data in the table.
(GRAPH CANT COPY)
Is there any relation between foot length and height?

Brandon Fox
Brandon Fox
Numerade Educator
01:01

Problem 9

Determine whether each relation is a function. Explain.
$$\{(-1,6),(4,2),(2,36),(1,6)\}$$

Brandon Fox
Brandon Fox
Numerade Educator
00:49

Problem 10

Determine whether each relation is a function. Explain.
$$\{(-2,3),(4,7),(24,-6),(5,4)\}$$

Brandon Fox
Brandon Fox
Numerade Educator
00:34

Problem 11

Determine whether each relation is a function. Explain.
$$\{(9,18),(0,36),(6,21),(6,22)\}$$

Brandon Fox
Brandon Fox
Numerade Educator
00:38

Problem 12

Determine whether each relation is a function. Explain.
$$\{(5,-4),(-2,3),(5,-1),(2,3)\}$$

Brandon Fox
Brandon Fox
Numerade Educator
00:58

Problem 13

Determine whether each relation is a function. Explain.
$$\begin{array}{|c|c|}\hline \text { Domain } & \text { Range } \\\hline-4 & -2 \\\hline-2 & 1 \\
\hline 0 & 2 \\\hline 3 & 1 \\\hline\end{array}$$

Brandon Fox
Brandon Fox
Numerade Educator
00:51

Problem 14

Determine whether each relation is a function. Explain.
$$\begin{array}{|c|c|}\hline \text { Domain} & \text { Range } \\\hline-1 & 5 \\\hline-2 & 5 \\\hline-2 & 1 \\
\hline-6 & 1 \\\hline\end{array}$$

Brandon Fox
Brandon Fox
Numerade Educator
00:47

Problem 15

Determine whether each relation is a function. Explain.
$$\begin{array}{|r|r|}\hline x & y \\\hline-7 & 2 \\\hline 0 & 4 \\\hline 11 & 6 \\\hline 11 & 8 \\\hline 0 & 10 \\
\hline\end{array}$$

Brandon Fox
Brandon Fox
Numerade Educator
01:04

Problem 16

Determine whether each relation is a function. Explain.
$$\begin{array}{|r|r|}\hline x & y \\\hline 14 & 5 \\\hline 15 & 10 \\\hline 16 & 15 \\\hline 17 & 20 \\\hline 18 & 25 \\
\hline\end{array}$$

Brandon Fox
Brandon Fox
Numerade Educator
01:10

Problem 17

Determine whether each relation is a function. Explain.
(GRAPH CANT COPY)

Brandon Fox
Brandon Fox
Numerade Educator
01:29

Problem 18

Determine whether each relation is a function. Explain.
(GRAPH CANT COPY)

Brandon Fox
Brandon Fox
Numerade Educator
00:51

Problem 19

Determine whether each relation is a function. Explain.
(GRAPH CANT COPY)

Brandon Fox
Brandon Fox
Numerade Educator
00:44

Problem 20

Determine whether each relation is a function. Explain.
(GRAPH CANT COPY)

Brandon Fox
Brandon Fox
Numerade Educator
01:05

Problem 21

Use the table that shows the number and size of farms in the United States every decade from 1950 to 2000.
(TABLE CANT COPY)
Is the relation (year, number of farms) a function? Explain.

Brandon Fox
Brandon Fox
Numerade Educator
00:29

Problem 22

Use the table that shows the number and size of farms in the United States every decade from 1950 to 2000.
(TABLE CANT COPY)
Describe how the number of farms is related to the year.

Brandon Fox
Brandon Fox
Numerade Educator
00:58

Problem 23

Use the table that shows the number and size of farms in the United States every decade from 1950 to 2000.
(TABLE CANT COPY)
Is the relation (number of farms, average size of farms) a function? Explain.

Brandon Fox
Brandon Fox
Numerade Educator
00:56

Problem 24

Is the relation (number of farms, average size of farms) a function? Explain.
Describe how the average size of farms is related to the year.

Brandon Fox
Brandon Fox
Numerade Educator
02:02

Problem 25

Tell whether each statement is always, sometimes, or never true. Explain.
A function is a relation.

Brandon Fox
Brandon Fox
Numerade Educator
01:51

Problem 26

Tell whether each statement is always, sometimes, or never true. Explain.
A relation is a function.

Brandon Fox
Brandon Fox
Numerade Educator
01:07

Problem 27

Use the table that shows how various wind speeds affect the actual temperature of $15^{\circ} \mathrm{F}.$
(TABLE CANT COPY)
Do the data represent a function? Explain.

Brandon Fox
Brandon Fox
Numerade Educator
00:55

Problem 28

Use the table that shows how various wind speeds affect the actual temperature of $15^{\circ} \mathrm{F}.$
(TABLE CANT COPY)
Describe how wind chill temperatures are related to wind speed.

Brandon Fox
Brandon Fox
Numerade Educator
01:07

Problem 29

RESEARCH Use the Internet or another source to find the complete wind chill table. Does the data for actual temperature and wind chill temperature for a specific wind speed represent a function? Explain.

Brandon Fox
Brandon Fox
Numerade Educator
01:39

Problem 30

Draw the graph of a relation that is not a function. Explain why it is not a function.

Brandon Fox
Brandon Fox
Numerade Educator
01:03

Problem 31

Describe three ways to represent a function. Show an example of each. Then describe three ways to represent a relation that is not a function and show an example of each.

Mike Gaerlan
Mike Gaerlan
Numerade Educator
03:01

Problem 32

The inverse of any relation is obtained by switching the coordinates in each ordered pair of the relation.
Determine whether the inverse of the relation $\{(4,0),(5,1),(6,2),(6,3)\}$ is a function.

Christopher Stanley
Christopher Stanley
Numerade Educator
03:01

Problem 33

The inverse of any relation is obtained by switching the coordinates in each ordered pair of the relation.
Is the inverse of a function always, sometimes, or never a function? Give an example to explain your reasoning.

Christopher Stanley
Christopher Stanley
Numerade Educator
00:52

Problem 34

The inverse of any relation is obtained by switching the coordinates in each ordered pair of the relation.
How can the relationship between water depth and time to ascend to the water's surface be a function? Include a discussion about whether water depth can ever have two corresponding times to ascend to the water's surface.

Jennifer Stoner
Jennifer Stoner
Numerade Educator
00:58

Problem 35

Which statement is true about the data in the table?
A The data represent a function.
B The data do not represent a function.
C As the value of $x$ increases, the value of $y$ increases.
D A graph of the data would not pass the vertical line test.
$$\begin{array}{|c|c|}\hline x & y \\\hline-4 & -4 \\\hline 2 & 16 \\\hline 5 & 8 \\\hline 10 & -4 \\\hline 12 & 15 \\
\hline\end{array}$$

Brandon Fox
Brandon Fox
Numerade Educator
00:56

Problem 36

F The water temperature stays the same as the depth increases.
G The water temperature decreases as the depth increases.
H The water temperature increases as the depth increases.
J The water temperature decreases as the depth decreases.

Brandon Fox
Brandon Fox
Numerade Educator
01:20

Problem 37

TECHNOLOGY The table shows the results of a survey in which middle school students were asked whether they ever used the Internet for the activities listed. Use the data to predict how many students in a middle school of 650 have used the Internet to do research for school.

Milo Kessler
Milo Kessler
Numerade Educator
01:00

Problem 38

Find each percent of change. Round to the nearest tenth, if necessary. Then state whether the percent of change is a percent of increase or a percent of decrease.
from $\$ 56$ to $\$ 49$

Brandon Fox
Brandon Fox
Numerade Educator
01:05

Problem 39

Find each percent of change. Round to the nearest tenth, if necessary. Then state whether the percent of change is a percent of increase or a percent of decrease.
from 110 mg to 165 mg

Brandon Fox
Brandon Fox
Numerade Educator
00:44

Problem 40

The length of a DNA strand is 0.0000007 meter. Write the length of a DNA strand using scientific notation.

Brandon Fox
Brandon Fox
Numerade Educator
00:32

Problem 41

Evaluate each expression if $x=4$ and $y=-1.$
$$3 x+1$$

Brandon Fox
Brandon Fox
Numerade Educator
00:18

Problem 42

Evaluate each expression if $x=4$ and $y=-1.$
$$2 y$$

Brandon Fox
Brandon Fox
Numerade Educator
00:19

Problem 43

Evaluate each expression if $x=4$ and $y=-1.$
$$y+6$$

Brandon Fox
Brandon Fox
Numerade Educator
00:44

Problem 44

Evaluate each expression if $x=4$ and $y=-1.$
$$20-4 x$$

Brandon Fox
Brandon Fox
Numerade Educator