Question

Which of the following relations is a function?
A. {(-4, 3), (-4, 2), (1, 9), (6, 7)}
B. {(-4, 3), (-2, 0), (2, 7), (3, 9)}
C. {(2, 1), (4, 2), (2, 3), (8, 4)}
D. {(0, 0), (0, 1), (2, 3), (4, 5)}

Answer 1

If you see the same x value used more than once, then it's not a function.

Answer 2

cool thanx