6 = r * (3-x)
7-5x = r (6)
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r = 6/(3-x)
6 r + 5 x = 7
=======================
[36 / (3-x)] + 5 x = 7
36 + 15x - 5 x^2 = 21 - 7 x
5 x^2 - 22 x - 15 = 0
(5x + 3)(x - 5) = 0
x = 5 or x = -3/5
you finish it
If (3-x) + (6) + (7-5x) is a geometric series, find two possible values for
a x
b the common ratio
c the sum of the GO.
2 answers
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