SOLUTION: Solve for x 3^7x=81^x+9

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Question 1071215: Solve for x 3^7x=81^x+9
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Written poorly, maybe: 3^7x=81^x+9
?

This would be unambiguous and more easily solvable:
3^(7x)=81^(x+9)

to appear, 3%5E%287x%29=81%5E%28x%2B9%29.
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3%5E%287x%29=%283%5E4%29%5E%28x%2B9%29

3%5E%287x%29=3%5E%284%28x%2B9%29%29

3%5E%287x%29=3%5E%284x%2B36%29

The exponents would be equal.
7x=4x%2B36
3x=36
highlight_green%28x=12%29