INTERMEDIATE ALGEBRA Class Notes Sections 7.1 and 7.2
Section 7.1 Chapter 7: Introduction to Relations and Functions Let’s work Exercise #19 from Section 5.1
Section 7.1 Exercise #7 Chapter 7: Introduction to Relations and Functions Section 7.1 Exercise #7 Let’s work Exercise #19 from Section 5.1
Write the slope-intercept form of the line. Then identify the slope and y-intercept.
Section 7.1 Exercise #31 Chapter 7: Introduction to Relations and Functions Section 7.1 Exercise #31
Section 7.1 Exercise #39 Chapter 7: Introduction to Relations and Functions Section 7.1 Exercise #39
Section 7.1 Exercise #45 Chapter 7: Introduction to Relations and Functions Section 7.1 Exercise #45
Section 7.1 Exercise #55 Chapter 7: Introduction to Relations and Functions Section 7.1 Exercise #55
The following table represents the median selling price, y, of new privately-owned one-family houses sold in the Midwest from 1980 to 2000. Let x represent the number of years since 1980. Let y represent price in thousands of dollars. Year Price in $1000 1980 x = 0 67 1985 x = 5 84 1990 x = 10 108 1995 x = 15 142 2000 x = 20 167
Year (x = 0 corresponds to 1980) 200 150 100 50 0 5 10 15 20 Year (x = 0 corresponds to 1980) Price (in $1000)
Year (x = 0 corresponds to 1980) 200 150 100 50 0 5 10 15 20 Year (x = 0 corresponds to 1980) Price (in $1000)
Year (x = 0 corresponds to 1980) 200 150 100 50 0 5 10 15 20 Year (x = 0 corresponds to 1980) Price (in $1000)
Year (x = 0 corresponds to 1980) 200 150 100 50 0 5 10 15 20 Year (x = 0 corresponds to 1980) Price (in $1000)
Year (x = 0 corresponds to 1980) 200 150 100 50 0 5 10 15 20 Year (x = 0 corresponds to 1980) Price (in $1000)
The median price in 2005 will be $192,000.
Section 7.2 Applications of Linear Equations Chapter 7: Introduction to Relations and Functions Section 7.2 Applications of Linear Equations Let’s work Exercise #19 from Section 5.1
Section 7.2 Exercise #5 Chapter 7: Introduction to Relations and Functions Section 7.2 Exercise #5 Let’s work Exercise #19 from Section 5.1
The average daily temperature in January for cities along the Eastern seaboard of the United States and Canada generally decreases for cities farther north. A city’s latitude in the Northern Hemisphere is a measure of how far north it is on the globe.
The average temperature, y, can be described by the equation where x is the latitude of the city. Average Daily Temperature(F) Jacksonville, FL 30.3 52.4 Miami, FL 25.8 67.2 Atlanta, GA 33.8 41.0 Baltimore, MD 39.3 31.8 Boston, MA 42.3 28.6 Atlantic City, NJ 39.4 30.9 New York, NY 40.7 31.5 Portland, ME 43.7 20.8 Charlotte, NC 35.2 Norfolk, VA 36.9 39.1
The average temperature, y, can be described by the equation where x is the latitude of the city. 100 80 60 40 20 20 30 40 50 Temperature Latitude
Which variable is the dependent b. Which variable is the independent variable?
Section 7.2 Applications of Linear Equations Chapter 7: Introduction to Relations and Functions Section 7.2 Applications of Linear Equations Let’s work Exercise #19 from Section 5.1
Section 7.2 Exercise #9 Chapter 7: Introduction to Relations and Functions Section 7.2 Exercise #9 Let’s work Exercise #19 from Section 5.1
This figure depicts a relationship between a person’s height, y (in inches), and the length of the person’s arm, x (measured in inches from shoulder to wrist). 100 90 80 70 60 50 40 30 20 10 3 6 9 12 15 18 21 24 28
The slope = 3.5 For each additional inch in length of a person’s arm, the person’s height increases by 3.5 inches.
Section 7.2 Exercise #11 Chapter 7: Introduction to Relations and Functions Section 7.2 Exercise #11 Let’s work Exercise #19 from Section 5.1
The cost to rent a car, y, for 1 day is $20 plus $0.25 per mile. Write a linear equation to compute the cost, y, of driving a car x miles for 1 day. or
The cost to rent a car, y, for 1 day is $20 plus $0.25 per mile. b. Use the linear equation to compute the cost of driving 258 miles in the rental car.
Section 7.3 Introduction to Relations Chapter 7: Introduction to Relations and Functions Section 7.3 Introduction to Relations Let’s work Exercise #19 from Section 5.1
Section 7.3 Exercise #7 Chapter 7: Introduction to Relations and Functions Section 7.3 Exercise #7 Let’s work Exercise #19 from Section 5.1
Write the relation as a set of ordered pairs. B C D E 1 2 3 4 5
Section 7.3 Exercise #11 Chapter 7: Introduction to Relations and Functions Section 7.3 Exercise #11 Let’s work Exercise #19 from Section 5.1
List the domain and range. B C D E 1 2 3 4 5
Section 7.3 Exercise #23 Chapter 7: Introduction to Relations and Functions Section 7.3 Exercise #23 Let’s work Exercise #19 from Section 5.1
Find the domain and range of the relations Find the domain and range of the relations. Use interval notation where appropriate.
Section 7.3 Exercise #35 Chapter 7: Introduction to Relations and Functions Section 7.3 Exercise #35 Let’s work Exercise #19 from Section 5.1
(Source: Centers for Disease Control) The percentage of male high school students, y, who participated in an organized physical activity for the year 1995 is approximated by y = –12.64x + 195.22. For this model, x represents the grade level (Source: Centers for Disease Control)
The percentage of male high school students, y, who participated in an organized physical activity for the year 1995 is approximated by y = –12.64x + 195.22. For this model, x represents the grade level Approximate the percentage of males who participated in organized physical activity for grades 9, 10, 11, and 12, respectively.
Grade 9, x = 9:
Grade 10, x = 10:
Grade 11, x = 11:
Grade 12, x = 12:
The percentage of male high school students, y, who participated in an organized physical activity for the year 1995 is approximated by y = –12.64x + 195.22. For this model, x represents the grade level b. Can we use this model to predict seventh-grade participation? Explain your answer.