The document discusses functions and non-functions through several examples of relations between x and y values. It provides tables and graphs of relations that illustrate functions, such as a y value being mapped to only one x value, as well as non-functions where a single x value is mapped to multiple y values or a y value is not mapped to any x values at all.

1. To be a function or not to be a function

2. Function Not a Function 12 6 10 5 8 4 6 3 4 2 2 1 Y X 10 5 4 4 8 3 5 1 4 2 2 1 Y X

3. Function Not a Function 8 4 20 8 6 Y -10 8 3 0 -3 X 8 4 20 8 6 Y -8 7 -2 0 -2 X

4. Function Not a Function (4,12) (5,15) (6,18) (7,21) (8,24) (4,12) (4,15) (5,18) (5,21) (6,24)

5. Function Not a Function 10 3 4 7 5 2 3 4 8 10 3 5 7 2 2 3 4 7 5

6. Function Not a Function -3 -2 -1 0 1 -6 -1 -0 3 15 -3 -2 -1 0 1 -6 -1 -0 3 15

7. Function Not a Function

8. Function Not a Function

9. Function Not a Function