You can put this solution on YOUR website! The question is appropriate if it reads as: (5^x-5^-x)/(5^x+5^-x) = 8
Assuming y = 5^x
(y - 1/y)/(y + 1/y) = 8
=>[(y^2-1)/y][(y^2 + 1)/y] = 8
=>(y^2 - 1)/(y^2 + 1) = 8
=>y^2 - 1 = 8y^2 + 8
=>7y^2 = -9
=>y^2 = -9/7
... y comes out to be imaginary, contradicts the property of exponetial function. Please check your maths and post it afresh.
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