Which relation is a function?

A.
{(1, 2); (1, 3); (3, 2); (4, 2)}

B.
{(1, 2); (2, 5); (3, 2); (4, 5)}

C.
{(1, 2); (2, 3); (3, 4); (2, 5)}

D.
{(1, 2); (2, 3); (3, 4); (1, 5)}

Question

Which relation is a function?	
 
 A.
{(1, 2); (1, 3); (3, 2); (4, 2)}
 
 B.
{(1, 2); (2, 5); (3, 2); (4, 5)}
 
 C.
{(1, 2); (2, 3); (3, 4); (2, 5)}
 
 D.
{(1, 2); (2, 3); (3, 4); (1, 5)}

godlovesme · Answer

(x,y)
if x is repeated in any of the above ordered pairs it's not a function

anonymous · Answer

So, you can eliminate  C, correct?

godlovesme · Answer

y c? @ionicallyrose

godlovesme · Answer

@ironicallyrose ***

holly00d1248 · Answer

2 repeating

holly00d1248 · Answer

Its B becaus etheres no x values repeating

godlovesme · Answer

oh sorry i didn't see that =0  u guys r correct :) @holly00d1248 & @ironicallyross

anonymous · Answer

Well, the question is asking for function and if x is repeated in any of the ordered pairs, it is not a function. Therefore, we can eliminate that.

godlovesme · Answer

@ironicallyrose ****

anonymous · Answer

Haha yeah :)

anonymous · Answer

Please be careful! Technically, it's not whether x is repeated. For example, if we added the ordered pair (3,2) to answer B, it would still be a function even though x=3 has been repeated. The definition of a function is a relation in which, for every value of x, there is a UNIQUE value of y.

holly00d1248 · Answer

very true @ospreytriple good catch

anonymous · Answer

Take answer A. For x=1, there are two corresponding value of y, y=2 and y=3. This relation, therefore, is not a function.