Question

Which of the following relations is a function?


{(-1, 1), (0, 3), (-1, 5), (2, 7)}

x y
0 5
5 0
-5 0
5 -5

0-4
2-6
3-7
9-13

There is also a graph I did not know how to copy and paste in question. So, if the answer is not here, it must be the graph with a line parallel to the "Y"

Answer 1

3rd one is a function :A function relates each element of a set
with exactly one element of another set
(possibly the same set).

Answer 2

I see that each output is different than the input, but the graph that I cant figure pout how to put here, shows one parallel line going through only ONE point on the graph, so wouldnt that be it??

Answer 3

1st one is not a function as there are two identical x values returning different y values.

Answer 4

second one is not a function for the same reason

Answer 5

exactly

Answer 6

for it to be a function, x can return one and only one y value.

Answer 7

In the first two examples an x returns two different y values.

Answer 8

please read what i said about the graph

Answer 9

can you do a quick sketch of the graph? dont worry about the numbers, just the x and y axis and the line

Answer 10

something like this?

Answer 11

If so, that is not a function either

Answer 12

that is what the line look sl.ike. vertical line on the #2 all the way down

Answer 13

thanks so much for your help. i get itnow. just found explanation in lesson also :)

Answer 14

in order for it to be a function it has to pass the "vertical line" test. If you can draw a vertical line through the graph anywhere and only cross the line once then it is a function

The bottom left one is not a function, the other three are.