SOLUTION: if the product of the first three terms of a geometric is -8 and the sum is 14/3, what is the common ratio of the sequence?

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Question 662357: if the product of the first three terms of a geometric is -8 and the sum is 14/3, what is the common ratio of the sequence?
Answer by sravanik2005(14) About Me  (Show Source):
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Let a/r,a,ar be the three terms
then product is a^3=-8 =>a=-2
and sum is -2/r-2-2r=14/3
-2-2r-2r^2=14r/3
-6-6r-6r^2=14r
6r^2+20r+6=0
3r^2+10r+3=0
r=-1/3 or -3