1. Writing a function rule You are traveling in a car at an average speed of 55mph. Whrite a function rule that describes the relationship between the time and the distance you travel. You can make a table to solve this problem. Input: time(h)1234 Output: distance(mi) 55110165220 Distance in miles = 55 x time in hoursWrite the function rule in words. d = 55t Use variables d and t for distance and time. Write a function rule for the relationship between the time and the distance you travel at an average speed of 62mi/h. d = 62t

2. The variables x and y are often used to represent input and output. You can describe the relationship between the values in the table in three ways. 1.Each output is 3 greater than the input 2.output = input + 3 3.y = x + 3 Input xOutput y 14 25 36 47

3. Using Tables to Analyze Functions Write a rule for the function represented by each table. xy 00 1-4 2-8 3-12 xy 0-3 1 21 33 When x = 0, y = 0, Each y equals -4 times x When x = 0, y = -3. Each y equals 2 times x, plus -3 The function rule is y = -4x + 0, or y = -4x The function rule is y = 2x + (- 3),or y = 2x – 3.

4. Write a rule for the function represented by the table below. x0123 y15913 y = 4x +1

5. Evaluating Functions Use the function y = -3x + 5. Find y for x = 0,1,2, and 3. Then make a table for the function. y = -3(0) + 5 = 5 Substitute 0,1,2,and 3 for x. y = -3(1) + 5 = 2 y = -3(2) + 5 = -1 y = -3(3) + 5 = -4 xy = -3x +5 05 12 2 3-4 List the values in a table.

6. Use the function y = 2x – 4. Find y for x = 0,1,2, and 3. Then make a table for the function. xy = 2x - 4 0-4 1-2 20 32 y = 2(0) -4 = -4 y = 2(1) -4 = -2 y = 2(2) -4 = 0 y = 2(3) -4 = 2