How do you find the next three terms in the geometric sequence 9, -3, 1, , ?

Each term is being divided by -3, so the next three terms would be:

-1/3, 1/9, -1/27

If you need an equation, it would be y=2x+8, y would be how long it grew, x being weeks.if you need how long he was asleep, it would be 4 weeks if he started with no beard, the equation would be x=8÷2if he did have a beard before hand, the equation would be 2w+x=8