Jonah and Janiyah work at the same plant nursery. Jonah has worked at the nursery for 6 more months than Janiyah. Together, they have worked at the nursery for 18 months. Write a system that could be used to determine the number of months each person worked.
1. x > y + 6
x + y < 18
2. y < 6
x + y > 18
3. y = 6
x + y = 18
4. x = y + 6
x + y = 18
