Please help by solving this equation 2*(7^x)-11=21*7^-x

Solve for x. Please write the whole procedure, because I know the answer is x=1, but I do not know how to get this result. Thank you in advance!
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1 Answer

2(7x)-11=21(7-x).

Multiply through by 7x:

2(72x)-11(7x)=21. 

2(72x)-11(7x)-21=0=(2(7x)+3)(7x-7). Since 7x cannot be negative, 7x=7​​​​​​​1 so x=1.

by Top Rated User (1.1m points)

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