SOLUTION: Evaluate each geometric series: -2-6-18-54..., N=7

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Question 748043: Evaluate each geometric series:
-2-6-18-54..., N=7
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
-2-6-18-54..., N=7
.
Nth term of geometric series:
an = a1*r^(n–1)
.
r = 3
n = 7
a1 = -2
.
a7 = (-2)*3^(7–1)
a7 = (-2)*3^6
a7 = (-2)*729
a7 = -1458
.
answer: -1458