SOLUTION: 2*(3)^2x-8=2*(3)^x+1

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Question 1046401: 2*(3)^2x-8=2*(3)^x+1
Answer by CubeyThePenguin(3113) About Me  (Show Source):
You can put this solution on YOUR website!
3^x = y

2y^2 - 8 = 2y + 1
2y^2 - 2y - 9 = 0

Use the quadratic formula: y = 1/2 + sqrt(19)/2 or 1/2 - sqrt(19)/2.

y has to be positive, so: x^3 = 1/2 + sqrt(19)/2

x = (1/2 + sqrt(19)/2)^(1/3)