document.write( "Question 267671: Please help with this equation:\r
\n" ); document.write( "\n" ); document.write( " log(base a) 5 = -3/4
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Algebra.Com's Answer #196698 by jsmallt9(3758)\"\" \"About 
You can put this solution on YOUR website!
\"log%28a%2C+%285%29%29+=+-3%2F4\"

\n" ); document.write( "Eventually we want an equation that says
\n" ); document.write( "a = some-number
\n" ); document.write( "So we need to get the \"a\" out of the base of the logarithm. We can so this by rewriting the equation in exponential form:
\n" ); document.write( "\"5+=+a%5E%28-3%2F4%29\"
\n" ); document.write( "Now we need to change the exponent on \"a\" to a 1 (because \"a%5E1+=+a\"). The quickest way to do this make clever use of the rules for exponents. I am going to raise both sides of the equation to the -4/3 power. (See what happens to see why.)
\n" ); document.write( "\"%285%29%5E%28-4%2F3%29+=+%28a%5E%28-3%2F4%29%29%5E%28-4%2F3%29\"
\n" ); document.write( "On the right side, the rule is to multiply the exponents. And what do you get when you multiply -3/4 and -4/3? Answer: 1!
\n" ); document.write( "\"5%5E%28-4%2F3%29+=+a\"
\n" ); document.write( "This may be an acceptable answer. If you want a decimal approximation you can use your calculator on the expression on the left side. Or, for an exact answer with rational denominators...
\n" ); document.write( "\"5%5E%28-4%2F3%29+=+a\"
\n" ); document.write( "\"1%2F5%5E%284%2F3%29+=+a\"
\n" ); document.write( "\"1%2Froot%283%2C+5%5E4%29+=+a\"
\n" ); document.write( "\"%281%2Froot%283%2C+5%5E4%29%29%28root%283%2C+5%5E2%29%2Froot%283%2C+5%5E2%29%29+=+a\"
\n" ); document.write( "\"root%283%2C+5%5E2%29%2Froot%283%2C+5%5E6%29+=+a\"
\n" ); document.write( "\"root%283%2C+5%5E2%29%2F5%5E2+=+a\"
\n" ); document.write( "\"root%283%2C+25%29%2F25+=+a\"\r
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