Identifying Functions or Not

Which of the following is NOT a function?

• 
• 
• 
• 

This table shows a function.

• true

• false

• Yes
• No

The following is not a function because...

• There are two values that equal 2.

• x = 10 and x = 40 has two values each.

• In the f(x) column, the 5 repeats.

• This table is actually a function.

Does this mapping diagram represent a function?

• No, because an input value goes to multiple output values

• Yes, because each input goes to one and only one output

• Function
• Not a Function

When a vertical line crosses the line of a function ​ (a)   the relation ​ (b)   a function.​ ​

• more than once

• is not

• never

• Yes
• No

• Yes
• No

• Yes
• No