SOLUTION: How do you solve for x when : log base81:5 + log base81: (2x-1)= 1/4

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Question 846344: How do you solve for x when : log base81:5 + log base81: (2x-1)= 1/4
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Log using base 81? Review the Change of Base formula(just in case), and use conventional notation.

highlight_green%28log%2881%2C5%29%2Blog%2881%2C2x-1%29=1%2F4%29.
You might think that change of base be necessary, but....
How far can this be solved WITHOUT changing bases?
Condensing the log expression, the left member,

log%2881%2C5%2A%282x-1%29%29=1%2F4

81%5E%281%2F4%29=5%282x-1%29

%283%5E4%29%5E%281%2F4%29=10x-5

3=10x-5
10x=3%2B5
10x=8
highlight%28x=4%2F5%29