Which of the following relations is a function?
A. { (1, 2), (1, 3), (1, 4), (1, 5) }
B. { (1, 3), (2, 3), (4, 3), (9, 3) }
C. { (5, 4), (-6, 5), (4, 5), (4, 0) }
D. { (6, -1), (1, 4), (2, 3), (6, 1) }

Question

Which of the following relations is a function?
A. { (1, 2),  (1, 3),  (1, 4),  (1, 5) }
B. { (1, 3),  (2, 3),  (4, 3),  (9, 3) }
C. { (5, 4),  (-6, 5),  (4, 5),  (4, 0) }
D. { (6, -1),  (1, 4),  (2, 3),  (6, 1) }

lgbasallote · Answer

A is not a function because 1 repeated
C is not a function because 4 repeated
D is not a function because 6 repeated

so it's B

lgbasallote · Answer

the function is the one where the x coordinate does not repeat

anonymous · Answer

Oh. Yeah. I just go t it mixed up when imagining it in my head. :)