document.write( "Question 1054592: 4^(5x+1) = 5^(4x-1) Must solve using logs \n" ); document.write( "

Algebra.Com's Answer #669789 by Edwin McCravy(20060) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Take logs of both sides:\r\n" );
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document.write( "Move the exponents in front of the logs as multipliers:\r\n" );
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document.write( "To make things easier, let single letters stand for\r\n" );
document.write( "those logs:\r\n" );
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document.write( "Let's substitute the letter A for log(4) and the letter\r\n" );
document.write( "B for log(5), substituting\r\n" );
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document.write( "log(4) = A and log(5) = B, the equation is simpler as\r\n" );
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document.write( "or\r\n" );
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document.write( "or\r\n" );
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document.write( "Solve for x:\r\n" );
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document.write( "Divide both sides by 5A+4B\r\n" );
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document.write( "Now get your calculator.  If you have a graphing calculator\r\n" );
document.write( "and know how, you can store log(4) as A and log(5) as B using\r\n" );
document.write( "the STO key, and type in  and press ENTER.\r\n" );
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document.write( "Or substitute log(4) for A and log(5) for B\r\n" );
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document.write( "You'll get x = -6.067672624\r\n" );
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document.write( "Edwin

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