Represent Functions

As Graphs

Vocabulary

• Function-A rule that establishes a relationship between two quantities, called the input and the output.

• Ordered pair- Each pair of input and output values.

• Point-An ordered pair of numbers that can be plotted on a graph.

Vocabulary

• Input- is the x coordinate.

• Output- is the y coordinate.(y axis, Vertical)

(x axis, Horizontal)

Graph a Function y = x + 1

• Domain (input x) {1,2,3,4,5}

Input x

Output y

1 2 3 4 5

Graph y = x + 1

• Ordered pairs (1,2)(2,3)(3,4)(4,5)(5,6)Y axis

X axis61 2 3 4 5

1

2

3

4

6

5

Graph a Function y = ½ x

• Domain (input x) {0, 2,4,6,8}

Input x

Output y

0 2 4 6 8

Graph y = ½ x

• Ordered pairs: (0,0) (2,1) (4,2) (6,3) (8,4)Y axis

X axis

00

1

2

3

4

5

1 2 3 4 5 6 7 8

Write a Function Rule

• Step one: Make a table

• Step two: Find the relationship between input and output

• Step three: Write a function rule

Input x

Output y

1

2

2

3

3

4

4

5

5

6

The Rule for the Function y=x + 1

• Ordered pairs: (1,2) (2,3) (3,4) (4,5) (5,6)

Y axis

X axis

1

2

3

4

5

6

0 1 2 3 4 5 6

Write a Function Rule

• Domain (input x) {0,1,4,6,10}

• Range (output y) {2,3,6,8,12}

Input x

Output y

0 1 4 610

2 3 6 8 12

Rule for the Function y = x + 2

• Ordered pairs: (0,2) (1,3) (4,6) (6,8)(10,12)

Y axis

X axis0 1 2 3 4 5 6 7 8 9 10

1

2

34567

89

1011

12

Questions/Practice

• Questions:

Plots and Functions

Chiquana

Daniel

Dylan

Frank

Isabella

Jonathan

Kiara

Forearm inches X Height inches y

Plot the points

• Y axis forearm length

X axis height

0