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Solve. Check for extraneous solutions. There might be no solution or there might be 2

Solve. Check for extraneous solutions. There might be no solution or there might be-example-1
User Fabius Wiesner
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1 Answer

5 votes
5 votes

Recall that:


\log _ba=\text{log}_bc\text{ }\Leftrightarrow\text{ a=c.}

Therefore,


(4n-7)=-3n\text{.}

Solving the above equation for n we get:


\begin{gathered} 4n-7=-3n, \\ 4n+3n=7, \\ 7n=7, \\ n=1. \end{gathered}

Now, recall that the logarithm of a negative number is not defined. If n=1, then -3n=-3<0, therefore there are no solutions.

Answer: No solution.

User Billc
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