Function Rules Tables and Graphs Lesson 5 3

Function Rules, Tables, and Graphs Lesson 5 -3 Algebra 1 Additional Examples 1 Model the function rule y = 3 x + 2 using a table of values and a graph. Step 1: Choose input value for x. Evaluate to find y. Step 3: Join the points to form a line. x 1 (x, y =y) x+2 3 – 3 y = 3 (– 3) + 2 = 1 0 y= 1 (0) + 2 = 2 3 (0, 2) 3 y = 1 (3) + 2 = 3 (3, 3) 1 3 Step 2: Plot the points for the ordered pairs. (– 3, 1)

Function Rules, Tables, and Graphs Lesson 5 -3 Algebra 1 Additional Examples At the local video store you can rent a video game for $3. It costs you $5 a month to operate your video game player. The total monthly cost C(v) depends on the number of video games v you rent. Use the function rule C(v) = 5 + 3 v to make a table of values and a graph. v C(v) = 5 + 3 v (v, C(v)) 0 C(0) = 5 + 3(0) = 5 (0, 5) 1 C(1) = 5 + 3(1) = 8 (1, 8) 2 C(2) = 5 + 3(2) = 11 (2, 11)

Function Rules, Tables, and Graphs Lesson 5 -3 Algebra 1 Additional Examples At a ball game they charge $2 for a hotdog. The function C(h) = 2 h describes the cost of h hotdogs. Use the points for each input value. Connect the points with a dashed line. h C(h) = 2 h (h, C(h)) 1 C(1) = 2 (1, 2) 2 C(2) = 2(2) = 4 (2, 4) 3 C(3) = 2(3) = 6 (3, 6) 4 C(4) = 2(4) = 6 (4, 8)

Function Rules, Tables, and Graphs Lesson 5 -3 Algebra 1 Additional Examples a. Graph the function y = |x| + 2. Make a table of values. x y = |x| + 2 (x, y) – 3 y = |– 3| + 2 = 5 (– 3, 5) – 1 y = |– 1| + 2 = 3 (– 1, 3) 0 y = |0| + 2 = 2 ( 0, 2) 1 y = |1| + 2 = 3 ( 1, 3) 3 y = |3| + 2 = 5 ( 3, 5) Then graph the data.

Function Rules, Tables, and Graphs Lesson 5 -3 Algebra 1 Additional Examples (continued) b. Graph the function ƒ(x) = x 2 + 2. Make a table of values. Then graph the data. x ƒ(x) = x 2 + 2 (x, y) – 2 ƒ(– 2) = 4 + 2 = 6 (– 2, 6) – 1 ƒ(– 1) = 1 + 2 = 3 (– 1, 3) 0 ƒ(0) = 0 + 2 = 2 ( 0, 2) 1 ƒ(1) = 1 + 2 = 3 ( 1, 3) 2 ƒ(2) = 4 + 2 = 6 ( 2, 6)