Question

which of the following is an example of a function

Answer 1

a function has one x value for each y-value

also a function cannot have one x-value with two y-values

But it can have two x-values with one y-value

do you also remember the vertical line test? You can use that if you want to plot the points and see :b

Answer 2

https://i.ytimg.com/vi/-xvD-n4FOJQ/hqdefault.jpg
https://upload.wikimedia.org/wikipedia/commons/f/fd/Vertical_line_test.png

Answer 3

also a function CANNOT have one x-value with two y-values

that means the answer can't be A, sorry :P

Answer 4

don't guess and look at the x-values and the y-values of each point