Question

Which relation is also a function?Select one of the options below as your answer:
A. {(1.5, 4) (2, 4) (2.5, 5) (3, 5) (2, 6)}....
B. {(-1, 3) (-1, 2) (-1, 4) (-1, 5) (-1, 6)}...
C. {(-2, 0) (1, 3) (-2, 1) (1, -3) (-2, 6)}...
D. {(1, 7) (2, 3) (4, 10) (6, 12) (8, 15)}

Answer 1

It'd be a function if there are no two pairs with THE SAME LEFT COORDINATE
and DIFFERENT RIGHT COORDINATES.

For example, the set of pairs in choice A is NOT a function because there is a (2,4) and a (2,6)

Answer 2

They have the same left coordinate (2) but different right coordinates (4 and 6)