Select all tables that represent a proportional relationship between x and y.

x 2 6 7 10
y 8 24 28 40


x 0 5 10 15
y 10 15 20 25


x –2 0 3 5
y –6 0 9 15


x 0 1 2 3
y 4 5 6 7


x –8 –6 –4 –2
y –9 –7 –5 –3