Question

Which relation does not represent a function?
Answer
(-5, 3), (-3, 1), (0, -4), (3, -6)
(2, 0), (4, 6), (6, 8), (10, 6)
(-3, 6), (-1, 1), (0, 1), (3, 7)
(-4, 2), (1, 5), (-2, 0), (1, 6)

Answer 1

plot your points, then see if a vertical line crosses them one at a time
If the vertical line crosses two at a time, then it fails the vertical line test

Answer 2

I will demonstrate with the first one