Questions on Algebra: Negative and Fractional exponents answered by real tutors!

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Question 159050: can you please help me find x?
2X10^-5 = (1+0.23x)^-3
Thank you in advance.: can you please help me find x?
2X10^-5 = (1+0.23x)^-3
Thank you in advance.
Answer by josmiceli(2162) About Me  (Show Source):
You can put this solution on YOUR website!
2*10^(-5) = (1 + .23x)^(-3)
multiply both sides by this expression:
(10^5)*(1 + .23x)^3
(2*10^(-5))*(10^5)*(1 + .23x)^3) = ((1 + .23x)^(-3))*(1 + .23x)^3)*(10^5)
This reduces to
2*(1 + .23x)^3 = 10^5
(1 + .23x)^3 = .5*10^5
Take the cube root of both sides
1 + .23x = (50000)^(1/3)
1 + .23x = 36.84
.23x = 36.84 - 1
.23x = 35.84
x = 155.83 answer
Hope I got it right