College Algebra: Logarithms, please help! (-.-) Solve for x: (look in comments)
\[\log _{7}(3x-9)-\log _{7}(2x-6)=0\]
is the right hand side really 0 ?
Yes, that's how it looks in my study packet.
The packet gave me 4 answer choices: a.) 3 b.) all real numbers c.) -3 d.) no solution
Okay send that negative log to right side and remove the log both sides
\[\log _{7}(3x-9) = \log _{7}(2x-6)\] \[3x-9 = 2x-6\] solve \(x\)
See, I thought the answer was 3 as well, but the answer is suppose to be D. I don't know why that is the answer...
you get \(x=3\) by solving but it could be an extraneous solution, so you need to plug that back intot he original equation and verify if it really works
Ohhh. I have a bad habit of not plugging the answer back into the equation. I'll try that now.
Keep in mind \(\log(x)\) as a real valued function is defined only for \(x\gt 0\)
I will, thank you very much!!
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