Identifying a Relation or a Function

What is the definition of function?

• Each input has outputs

• Each input has exactly one output

• Each output has exactly one input

• A list of x-values and y-values

A set of ordered pairs is called what?

• An Expression

• A Relation

• A Function

• The Vertical Line Test

Which relation is not a function?

• {(1,-5), (3,1), (-5,4), (4,-2)}

• {(2,7), (3,7), (4,7), (5,8)}

• {(1,-5), (-1,6), (1,5), (6,-3)}

• {(3,-2), (5,-6), (7,7), (8,8)}

Which relation is a function?

• {(0,1), (1,2), (3,3), (3,4)}

• {(0,2), (1,3), (2,3), (3,2)}

• {(1,3), (2,2), (2,0), (3,4)}

• {(1,2), (2,2), (3,2), (1,3)}

Given: {(5, 2), (7, 4), (9, 10), (x, 5)}, which of the following values substituted for x will make this relation a function?

• 7

• 9

• 4

• 5

Is this graph a function or not a function? 

• Function
• Not a Function

• Function
• Not a Function

Is this graph a function or not a function? 

• Function 
• Not a Function 

Which graph is not a function?

• Graph 1

• Graph 2

• Graph 3

• Graph 4

Which graph is a function?

• Graph 1
• Graph 2
• Graph 3
• Graph 4