1. Review Write as ax + b = 0 and then as y = ax + b. 5x + 2 = 8
Solve algebraically and then graph. 6x + 3 = -9

2. 4.8 Functions and Relations

3. Notes Function: input (x) has exactly one output (y).
Relation: pairing of numbers in a set. Domain: x coordinate, input, independent Range: y coordinate, output, dependent
Function: input (x) has exactly one output (y).
2 ways to tell if function
Mapping diagram
Vertical line test

4. Does the graph represent a function?

5. Does the graph represent a function?

6. Is the relation a function?

7. Is the relation a function?

8. Information Function notation: remove y, replace with f(x)
f(x) means f of x

9. Function Notation Given g(x) = 4x – 5. Find values.
g(x) when x = 2
g(-10)
x when g(x) = 19
g(x) when x = -1

10. Function Notation Given f(x) = -3x + 1. Find values.
f(x) when x = -1
f(x) when x = 5
x when f(x) = -17
f(-20)

11. Graph the function
F(x) = 2x - 5
G(x) = 2/3x - 1

12. Graph the function
F(x) = -4x + 3
G(x) = 1/2x + 2

13. Find the slope of the function
F(2) = 4, F(0) = 6
F(-1) = -4, F(-2) = 0

14. Find the slope of the function
F(1) = 3, F(3) = 7
F(-3) = 7, F(2) = -3

15. Wrap up
Questions/Comments Hw: text pg. 259, #’s: 2-48 evens