1. 3.3 Linear Functions Objectives The student will be able to: 1. To determine if a relation is a function. 2.To find the value of a function. Indicators: PFA #1, PFA#3, PFA#4, PFA#7, PFA#8, PFA#9 Designed by Skip Tyler, Varina High School Modified by Anny Lin, Crestwood Middle School

2. Given the domain {-2, -1, 0, 1, 2}, graph 4x-y=4 by making a table. xy=y(x,y)

3. (-2, -12) (-1,-8) (0,-4) (1,0) (2,4)

4. Is there an easy way to graph an equation?

5. Graph 3x+2y=9 using the x- intercept and y-intercept.

7. Work on P159 #27-29. Graph the equation by using x-intercept and y-intercept.

8. ANALYZE GRAPHS The purchase of a ride card at the zoo allows children to ride the rides and have their card punched each time. The value of the card is shown in the graph. a. Determine the x-intercept, y-intercept, and zero. b. Describe what the intercepts mean. The x-intercept is 5 because it is the coordinate where the line crosses the x-axis. The zero of the function is also 5. The y-intercept is 20 because it is the coordinate of the point where the line crosses the y-axis. The x-intercept 5 means that after 5 rides, the ride ticket has a value of $0. The y-intercept of 20 means that at time 0, or before any rides were ridden, the ticket had a value of $20. http://glencoe.mcgraw-hill.com/sites/0078738229/student_view0/chapter3/lesson3/extra_examples.html

9. ANALYZE TABLES Tanya is driving 65 miles per hour. The table shows the function relating the distance remaining on her trip and the number of hours she has driven. a.Determine the x-intercept, y-intercept, and zero of the graph of the function. x-intercept = 5 5 is the value of x when y = 0. y-intercept = 325 325 is the value of y when x = 0. zero = 5 The zero of the function is the x-intercept of the graph.

10. b. Describe what the intercepts mean. The x-intercept 5 means that after 5 hours, the distance remaining is 0, or she has reached her destination. The y-intercept 325 means that she had 325 miles to drive at time 0, or before she started her trip.

11. In order to prepare for the upcoming snow store, Abby went to Blockbuster. Movies cost $6 and Wii games cost $3. She spent $30 renting movies and Wii games. The equation that represents x movies and y Wii games is 6x+3y=30, where x=number of movies rented and y=number of Wii games rented. a)Graph the equation. b)Find the x-intercept. Explain what the x-intercept means in this problem.

15. Group Work

16. Finish the worksheet as homework.