document.write( "Question 4694: I have a couple of questions that I need help with:\r
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\n" ); document.write( "\n" ); document.write( "1. Solve for x:
\n" ); document.write( " ln7 + ln(x-3) = ln(x + 15)\r
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\n" ); document.write( "\n" ); document.write( "2. Solve for x:
\n" ); document.write( " 28 = 19 + 12^(x-7)
\n" ); document.write( " **The (x-7) is an exponent for the number 12\r
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\n" ); document.write( "\n" ); document.write( "3. Solve for x:
\n" ); document.write( " e^(3x-4) = 1/e^(x-12)
\n" ); document.write( " **The (3x-4) and (x-12) are both exponents\r
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\n" ); document.write( "\n" ); document.write( "4. Use the properties of logarithms to write 3lnx^2 + ln(2x-4)-ln(3x-6) as a single logarithm.\r
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\n" ); document.write( "\n" ); document.write( "To whoever is kind enough to help with answering these problems: Thank you and I would appreciate it if you could show your work so I can better understand how to do these types of problems myself. Thanks again!
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Algebra.Com's Answer #2201 by rapaljer(4671)\"\" \"About 
You can put this solution on YOUR website!
1. ln7 + ln(x-3) = ln(x + 15)\r
\n" ); document.write( "\n" ); document.write( "First get the variables on one side (the right side) by subtracting ln(x-3) from each side.
\n" ); document.write( "ln 7 = ln(x+15) - ln(x-3)\r
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\n" ); document.write( "\n" ); document.write( "Use the property of logs to express the right side as a log of a single quantity: \"+ln+M+-+ln+N+=+ln+%28M%2FN%29+\"
\n" ); document.write( "\"ln+7+=+ln+%28%28x%2B15%29%2F%28x-3%29%29+\"\r
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\n" ); document.write( "\n" ); document.write( "Because ln A = ln B, you can say that A=B. In the same way,
\n" ); document.write( "\"7+=+%28x%2B15%29%2F%28x-3%29+\"\r
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\n" ); document.write( "\n" ); document.write( "Multiply both sides of the equation by (x-3):
\n" ); document.write( "\"7%28x-3%29+=+%28x%2B+15%29+\"
\n" ); document.write( "\"7x+-+21+=+x+%2B+15+\"
\n" ); document.write( "\"6x+=+36\"
\n" ); document.write( "\"x=6\"\r
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\n" ); document.write( "\n" ); document.write( "Check to make sure x= 6 doesn't give you the log of a negative. It does not.\r
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\n" ); document.write( "\n" ); document.write( "2. \"28+=+19+%2B+12%5E%28x-7%29\"\r
\n" ); document.write( "\n" ); document.write( "Subtract 19 from each side of the equation:
\n" ); document.write( "\"9+=+12%5E%28x-7%29\"\r
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\n" ); document.write( "\n" ); document.write( "Take the ln of each side:
\n" ); document.write( "\"ln+%289%29+=+ln+%2812%5E%28x-7%29%29+\"\r
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\n" ); document.write( "\n" ); document.write( "By law of logarithms:
\n" ); document.write( "\"ln+%289%29+=+%28x-7%29+%2A+ln+%2812%29\"\r
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\n" ); document.write( "\n" ); document.write( "By distributive property:
\n" ); document.write( "\"ln+%289%29+=+x+ln%2812%29+-+7+ln%2812%29+\"\r
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\n" ); document.write( "\n" ); document.write( "Add 7 ln (12) to each side:
\n" ); document.write( "\"ln+%289%29+%2B+7+ln+%2812%29+=+x+ln+%2812%29+\"\r
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\n" ); document.write( "\n" ); document.write( "Divide both sides by ln (12)\r
\n" ); document.write( "\n" ); document.write( "\"+%28ln+%289%29+%2B+7+ln+%2812%29%29%2F+%28ln+%2812+%29%29+=+x+\"\r
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\n" ); document.write( "\n" ); document.write( "I'm very sorry, that's all I have time for. Maybe someone else will do the others, or perhaps you can repost them.\r
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\n" ); document.write( "\n" ); document.write( "R^2 at SCC
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