Functions and Graphs

Is this a function?

• Yes

• No

Is this a function?

• Yes

• No

Is this a function?

• Yes

• No

Is this mapping a function or not a function? 

• Function

• Not a Function

Is this graph a function or not a function? 

• Function 

• Not a Function

Is this table a function or not a function? 

• Function

• Not a Function

• A

• B

• C

• D

Is the relation a function? Why.

• Yes, because the x-value 11 has two y-values pair with it.

• Yes, because each x-value has only one y-value paired with it.

• No, because the x-value 11 has two y-values pair with it.

• No, because each x-value has only one y-value paired with it.

What is the definition of function?

• Has inputs and outputs

• Every input has only ONE output

• Inputs have different outputs every time

• x-values and y-values

How do you determine if a graph is a function?

• look at the y-values, if they repeat, it's not a function

• Use the "vertical line" test aka "pencil test"

• Look at you x-values, if they repeat it is a function

• Use the horizontal line test