Question

Which of these are functions and which are not?

A (-1,0),(3,0),(5,2)
B (3,2),(5,-4),(5,1)
C (0,3),(2,5),(2,6),(3,7)
D (-1,3),(0,5),(1,5),(5,7)

Answer 1

A&C are both functions. B&D are not. A&C do not have any numbers that are repetitive.