Identifying Functions from Tables & Graphs

Decide whether or not each table or graph below could represent a function. If not, circle what tells you it’s not a function.
In a function, there’s exactly one y-value for each x-value. Any table or graph with more than one y-value for the same x-value, can’t represent a function.

x	y
-2	5
0	2
2	4
4	7
6	8

diagonal line sloping upward

x	y
0	7
1	2
1	3
2	6
3	-8

Function or Not?

graph of a curve that comes in to the origin from the top right and exits as a line toward the bottom right

x	y
-1.5	-2
-1	-1
-0.5	0
0	1
0.5	2

scatter plot

Function or Not?

x	y
-1	1.5
0	1.5
1	1.5
2	1.5
3	1.5

graph of an S-shaped curve, opening up and down

x	y
8	1
5	2
4	3
5	4
8	5

Function or Not?

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