document.write( "Question 549482: I am trying to help my niece with an equation. Solving with logarithms, the equation is 5^x=4^(x+3). I cannot remember for the life of me how to solve this..Can you help? \n" ); document.write( "
Algebra.Com's Answer #357784 by lwsshak3(11628)\"\" \"About 
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I am trying to help my niece with an equation. Solving with logarithms, the equation is 5^x=4^(x+3). I cannot remember for the life of me how to solve this.
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\n" ); document.write( "using the exponent rule for logs:
\n" ); document.write( "xlog5=(x+3)log4
\n" ); document.write( "x/(x+3)=log4/log5
\n" ); document.write( "using calculator
\n" ); document.write( "x/(x+3)≈.8614
\n" ); document.write( "x=.8614x+3*.8614
\n" ); document.write( "x-.8614x=2.5841
\n" ); document.write( ".1386x=2.5814
\n" ); document.write( "x=2.5814/.1386=18.6185
\n" ); document.write( "Check:
\n" ); document.write( "5^x=5^18.6185=1.0322*10^13
\n" ); document.write( "4^(x+3)=4^(21.6185)=1.0366*10^13
\n" ); document.write( "difference due to rounding errors
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