1. 4.5 – Functions Textbook pg. 268 Objective:
The student will identify functions in order to prepare for writing and graphing functions.

2. function: special type of relation – every x-value only has one specific y-value (x can’t repeat)
FUNCTION NOT A FUNCTION x x y y
Is it a function?
1) 2) 3)
x y
1 1
0 5

3. Vertical Line Test: determines if a graph is a function - Move an imaginary “vertical line” from left to right. If the “line” only crosses the graph at one point the whole time, it IS a function.
Is it a function? 4)

4. 5) A shop rents canoes for a $7 equipment fee plus $2 per hour, with a maximum charge of $15. Express the number of hours (x) and the cost (y) as a relation in a table by finding the cost to rent a canoe for 1, 2, 3, 4, and 5 hours. Is this relation a function? Explain

5. 6) You can burn 6 calories a minute bicycling.
Let x = minutes and y = calories burned.
Write ordered pairs to show how many calories are burned when you bike for 30, 60, 90, 120, or 180 minutes.
State the domain and range. Is it a function?

6. Name Date Period 4.5 – pg. 271 #12-15, 24-26, 31-32, 35