Which relation is a function?

A.
{(7, 12), (1, –5), (3, –10), (2, –5)}

B.
{(1, 2), (1, 5), (1, –1), (1, 4)}

C.
{(–3, 4), (–2, 5), (0, 9), (0, 12)}

D.
{(8, –1), (2, –1), (3, 8), (2, 5}

Question

Which relation is a function?	
 
 A.
{(7, 12), (1, –5), (3, –10), (2, –5)}
 
 B.
{(1, 2), (1, 5), (1, –1), (1, 4)}
 
 C.
{(–3, 4), (–2, 5), (0, 9), (0, 12)}
 
 D.
{(8, –1), (2, –1), (3, 8), (2, 5}

anonymous · Answer

do u know what a function is to begin with?

anonymous · Answer

uhh... kinda...? i guess not really i cannot lie

anonymous · Answer

a function relates an input to an output

anonymous · Answer

',:( im dumb- x is input and y is output... right?

anonymous · Answer

yes

anonymous · Answer

does that help u?

anonymous · Answer

Sorry... yes it did! but how do I know which is right? it asks if it is a function... but how do i find that???

anonymous · Answer

@the_princess

anonymous · Answer

@googlesun

anonymous · Answer

he should be able to help.....i hope

anonymous · Answer

he's not online...

anonymous · Answer

if u hover over his name it says he is offline

anonymous · Answer

ugh he was just online

anonymous · Answer

then i hope @brandon1290 can help.....plz say yes

anonymous · Answer

he's online!!!!

anonymous · Answer

lol ik i was talking to him

anonymous · Answer

Gosh I wish I could help I can't remember this it was in 8th  and I'm in 10th