Question

@hartnn Can you help me with a function question?

Answer 1

sure, i'll try :)

Answer 2

Which relation is a function?


A.


{(1, 2), (1, 5), (1, –1), (1, 4)}


B.


{(7, 12), (1, –5), (3, –10), (2, –5)}


C.


{(8, –1), (2, –1), (3, 8), (2, 5}


D.


{(–3, 4), (–2, 5), (0, 9), (0, 12)}

Answer 3

a relation is a function, when x value is paired with ONLY ONE of the y value

Answer 4

http://www.regentsprep.org/regents/math/algebra/ap3/lfunction.htm

Answer 5

D?

Answer 6

in D, 0 is paired with both 9 and 12
so not D

Answer 7

The answer is B because when you have a function it must not happen (1,9) and (1,5) for an example. So one element cannot have two different images. In A) You have (1,2), (1,-1), (1,4) That is not function. In C) There is (2,-1) (2,5) Again it's not a function D (0,9) (0,12) it's not a function. Did you get it?

Answer 8

Oh. I get it now. Thanks guys!

Answer 9

I thought you couldn't supposed to count the ones. :p

Answer 10

Another way around, for example (1,4) and (3,4) is possible and it is a function, In B there is 1,-5 and 2,-5 it is allowed and it is a function. Hope it was helpful