For each graph below, state whether it represents a function

Answer:
Functions - 3 and 6
Not Functions - 1, 2, 4 and 5,
Step-by-step explanation:
Let us number the graphs as, 1 2 3
4 5 6
Now, 'A function is a relation in which every element of the domain have a unique image in the co-domain'.
Graphically, to check whether the relation is a function, we use 'Vertical Line Test'.
It states that, 'If a vertical line passing through the graph cuts the graph at exactly one point, then the relation is a function'.
So, according to the options, we get,
In graphs 1, 2, 4 and 5, if we plot a vertical line passing through the graph, it cuts at more than one points.
That is, there are different image for the same element.
Thus, we have,
Functions - 3 and 6
Not Functions - 1, 2, 4 and 5,
Answer:
Graph number 3, 4 and 6.
Step-by-step explanation:
First , lets numbering the graph (as given figure) as, 1, 2, 3,
4, 5, 6.
We know that a function is a special type of relation in which every element of the the domain have a unique image in the co-domain . If we check all given graph with the help of vertical line test , then we get the given graph is a function or not.
In vertical line test - if a vertical line (vertical line drown at each point of domain ) passing through the graph cut the graph at exactly one point, then the relation is a function.
Now we test and observe the graph with the help of vertical line test, we gate the graph number 3, 4 and 6 are the function because a vertical line passing through the graph , it cuts at only one point (it valid for all point of domain ), and the graph number 1, 2 and 5 are not a function because a vertical line passing through the graph, it cuts at more than one point (it valid for at list one point of domain)