Question

Which relation is a function?
A.
(5, –2), (4, 6), (–3, –2), (0, 4)
B.
(–1, –2), (3, –5), (–1, –5), (2, –2)
C.
(4, 3), (3, 2), (–1, 5), (4, 0)
D.
(–4, –4), (3, –3), (–4, 4), (–3, 3)

Answer 1

function is the relation for which works the following:
1) function has values on all domain
2) function has only 1 value for 1 value of x

Answer 2

so find the relation that has only 1 value of certain x

A) this set is function
B) this set also function, because (-1, -2) and (-1, -5) have same x-ccordinate and different y-coordinate

Answer 3

C) this set isn't function because of (4, 3) and (4, 0)
D) this set also isn't function because of (-4, -4) and (-4, 4)

Answer 4

So which one would be correct? sorry I'm a bit confused

Answer 5

a function will not have any x values that are the same....they can have repeating y values, but not repeating x values.

Look at this one...
(-4,-4) , (3,-3) , (-4,4) , (-3,3)
notice that 2 of these have an x value that is repeating...you have 2 x values that are -4...a function cannot have repeating x values....this one is not a function
understand ? So you need to find the one that does not have any x values that are the same

Answer 6

so b?

Answer 7

B has 2 x values that are -1....these are repeating x values...this is NOT a function

Answer 8

so A?

Answer 9

yes...it's A....there is no repeating x values....it can have repeating y values, just not repeating x values

Answer 10

Ohhh thats what I was still confused about thanks so so much!

Answer 11

no problem :)