how do i do this???/

Start at the big tree, and take the instructions
one at a time:

1). Walk 15 west.

2). From there, turn around and walk 2 east.

3). From there, walk 7 more east.

Where are you from the big tree now ?

Aren't you 6 west of it ?

I mean, let's see some common sense here !

If you take the Western direction as the positive direction and the Eastern direction as negative one, then,Distance traveled to the West = +15 mDistance traveled to the east = (-2 m) + (-7 m ) = -9 m Total Displacement = 15 m + (-9) m Total displacement = 6 mSince the total displacement is positive, the displacement will be in the Western direction.So, option  (D) is correct.