2. Notes Over 4.8 Identifying Functions A relation where each input has exactly one output. Function Decide whether the relation is a function. If it is a function, give the domain and the range. 1. Input Output 2 1 4 3 5 8 7 Not a function, because 4 goes to both 3 and 5

3. Notes Over 4.8 Identifying Functions A relation where each input has exactly one output. Function Decide whether the relation is a function. If it is a function, give the domain and the range. 2. Input Output 1 2 4 3 9 4 16 A function, because every input goes to only one output Domain: the input Range: the output 1, 2, 3, 4 1, 4, 9, 16

4. Notes Over 4.8 Identifying Functions A relation where each input has exactly one output. Function Decide whether the relation is a function. If it is a function, give the domain and the range. 3. Input Output 1 2 4 3 6 4 8 A function, because every input goes to only one output Domain: the input Range: the output 1, 2, 3, 4 4, 6, 8

5. Notes Over 4.8 Identifying Functions The equation y = 3x – 4 becomes f(x) = 3x – 4, where the solution (x, y) becomes (x, f(x)). Function Notation Evaluate the function when x = 3, x = 0, x = - 2.

6. Notes Over 4.8 Identifying Functions The equation y = 3x – 4 becomes f(x) = 3x – 4, where the solution (x, y) becomes (x, f(x)). Function Notation Evaluate the function when x = 3, x = 0, x = - 2.

7. Notes Over 4.8 Identifying Functions The equation y = 3x – 4 becomes f(x) = 3x – 4, where the solution (x, y) becomes (x, f(x)). Function Notation Evaluate the function when x = 3, x = 0, x = - 2.

8. Notes Over 4.8 7. While on vacation, your family traveled 2040 miles in 6 days. Your average speed was miles per day. Verbal Model Distance traveled Average speed Time Labels:Distance traveled = f ( t ) Average speed = 340 miles per day Time = t days Writing and Using a Linear Function a. Write a linear function that models the distance that your family traveled each day. 340

9. Notes Over 4.8 7. While on vacation, your family traveled 2040 miles in 6 days. Your average speed was 340 miles per day. Writing and Using a Linear Function b. Use the model to find the distance traveled after 1.5 days of travel.

10. Notes Over 4.8 7. While on vacation, your family traveled 2660 miles in 7 days. Your average speed was miles per day. Verbal Model Distance traveled Average speed Time Labels:Distance traveled = f ( t ) Average speed = 380 miles per day Time = t days Writing and Using a Linear Function a. Write a linear function that models the distance that your family traveled each day. 380

11. Notes Over 4.8 7. While on vacation, your family traveled 2660 miles in 7 days. Your average speed was 380 miles per day. Writing and Using a Linear Function b. Use the model to find the distance traveled after 1.5 days of travel.

12. Notes Over 4.8