SOLUTION: Im really bad at math. HELP Find a5 and An for each geometric sequence. a2=-4,r=3

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Question 213500: Im really bad at math. HELP Find a5 and An for each geometric sequence. a2=-4,r=3
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the r is the RATIO of the geometric sequence

r = 3 means that each term is 3 times the previous term

a2 = -4; so a3 = -12, a4 = -36, and a5 = -108

the general term (An) is the first term, multiplied by the ratio raised to the n-1 power

An = a1 * r^(n-1)

in this case ___ An = (-4/3) * 3^(n-1)