SOLUTION: Sum of second and third is 6, third and fourth is -12. Find the common ratio

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Question 1075177: Sum of second and third is 6, third and fourth is -12. Find the common ratio
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
first term x
common ratio r

system%28xr%2Bxr%5E2=6%2Cxr%5E2%2Bxr%5E3=-12%29

Dividing second equation by first equation and simplifying.
r%5E2%2B3r%2B2=0
%28r%2B1%29%28r%2B2%29=0
r=-2--------------- the ratio.