Answer:
-21
Step-by-step explanation:
if for s(n) = -3-3n
then s(6) = -3-3*6 = -3-18 = -21
Hey there!
You are trying to find the perimeter of triangle ABC. Each side is 2. Since there are 3 sides on a triangle, multiply 2 by 3 to get 6. You do not need the centroid for this problem.
I hope this helps!