Functions

Warm UpSolve each equation.

1. 2x – 6 = 222. 3 + 5x = -323. X + 29 = 144. 6x – 5 – 4x = 17

x = 14 x = - 7x = -15

x = 11

What is a Function?

What is a Function?Each input value gives back exactly one output value.

Example: Input 7 into y = 2x + 9. y = 2(7) + 9

y = 23Input is 7 output is 23.

x = 7

Find the output when given the input for the function. y = x - 5

Remember x is the input and y is the output.-6

-5-4-3

Complete the function table.

-1 - 10

0 - 10

1 - 10

2 - 10

- 11

- 10

- 9

- 8

Another name for the input (x value) is domain.

Another name for the output (y value) is range.

What is the domain? What is the range?

(-3, 8), (0,7), (-4,-6), (2, -5)

Domain = - 4, - 3, 0, 2

Range = - 6, - 5, 7, 8

{10, 40, 61}

Function Tables and Graphs

Make a table and graph the function.

y = 3x + 71

-2

0-1

14

107

Choose values for the domain.

Find the range.

Make a table and graph the function. y = -2x + 1

210

-1

-3-1

31

Make a table and graph the function. y = x - 3

10

2

-1

-2-3

-1

-4

ClosureWhat numbers would you choose for the domain values of the function y = x + 1? Why?