Question

Please help will fan & medal!
Which of the following relations is a function?

{ (1, 2), (1, 3), (1, 4), (1, 5) }

{ (1, 3), (2, 3), (4, 3), (9, 3) }

{ (5, 4), (-6, 5), (4, 5), (4, 0) }

{ (6, -1), (1, 4), (2, 3), (6, 1) }

Answer 1

B
function = 2(x)
y-4

Answer 2

You can only have one input value (x) for every output value (y). So imagine you have a machine. If you put in only one x-value, it gives you only one y-value. Now lets try using this machine with a relation I came up with: {(1,2)(2,3)(2,4)}
So if you put in a 1 you get out a 2
If you put in a 2 you get out a 3
If you put in a 2 you get out a 4
Now, this doesn't make sense, because the machine can only give you one input value for every output value. Therefore, if there are repeating x-values, it is not a function, because you will have to graph the same x-value to more than one y-value.

And just to make this less confusing in case it is:
x/x-value = input/input value
y/y-value = output/output value

Hope this helps and I'm here if you have questions! :)

Answer 3

Thank you so much! :) @bishop.courtney2014 & @HorseGirl80

Answer 4

You're welcome! And thanks for the medal! :D

Answer 5

I plugged in the wrong number possibly too i think. I thing=k your right @HorseGirl80

Answer 6

Thanks! This is the first question I've ever answered, so that boosts my confidence! lol ;D