Respuesta :

pchen28

Answer:

The numbers increase by 3

Step-by-step explanation:

The difference between all the numbers in the sequence have a gap of 3

9 and 12 --gap of 3

12 and 15--gap of 3

18 and 21--gap of 3

21 and 24--gap of 3

SpittingFatLama

Answer

y=3+ before

Step-by-step explanation:

you add 3 to every number