Here, I'll help you a little
rewrite the equation as -6k/5 = 12
multiply both sides by 5
-6k=60
divide both sides by -6 to isolate k
k = -10
Hope this helps :)
In the attachement, there is what I came up with so far. I think that finding 'a' is non-trivial, if possible at all.
- the area of a circle
- the area of a circular segment
The answer is 64. Hope it helps you
Answer: 15309
hope this helps, the nth term calulation is (7/3) times 3^n