document.write( "Question 1117690: So I have to solve this equation by using logarithms. I am so lost. \r
\n" ); document.write( "\n" ); document.write( "2.5^x=34.1^(2x+7) \n" ); document.write( "
Algebra.Com's Answer #732812 by rothauserc(4718)\"\" \"About 
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2.5^x = 34.1^(2x+7)
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\n" ); document.write( "rewrite both sides of = using fractions
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\n" ); document.write( "(5/2)^x = (341/10)^(2x+7)
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\n" ); document.write( "take natural logarithms of both sides and use the identity log(a^b) = b * log(a)
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\n" ); document.write( "log(5/2) * x = log(341/10) * 2x+7
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\n" ); document.write( "rewrite terms on the right side of =
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\n" ); document.write( "log(5/2) * x = 2 * log(341/10) * x + 7 * log(341/10)
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\n" ); document.write( "subtract 2 * log(341/10) * x from both sides of = and isolate x
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\n" ); document.write( "(log(5/2) - 2 * log(341/10)) * x = 7 * log(341/10)
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\n" ); document.write( "now solve for x
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\n" ); document.write( "x = (7 * log(341/10)) / (log(5/2) - 2 * log(341/10))
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\n" ); document.write( "x = -4.0221
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