document.write( "Question 209259: Make x the subject of this formula:\r
\n" ); document.write( "\n" ); document.write( "a = b^x
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Algebra.Com's Answer #158185 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
\"a+=+b%5Ex\" if and only if \"log%28b%2Ca%29+=+x\"
\n" ); document.write( "example:
\n" ); document.write( "\"8+=+2%5E3\" if and only if \"log%282%2C8%29+=+3\"
\n" ); document.write( "-----
\n" ); document.write( "you can solve for \"log%282%2C8%29+=+3\" using your calculator by converting the base to 10 which the calculator can handle.
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\n" ); document.write( "the formula for doing that is:
\n" ); document.write( "\"log%28b%2Cx%29+=+log%28c%2Cx%29%2Flog%28c%2Cb%29\"
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\n" ); document.write( "in this particular case, we have x = 8 and b = 2 and c = 10 and the formula becomes:
\n" ); document.write( "\"log%282%2C8%29+=+log%2810%2C8%29%2Flog%2810%2C2%29\"
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\n" ); document.write( "using your calculator:
\n" ); document.write( "\"log%2810%2C8%29+=+.903089987\"
\n" ); document.write( "and:
\n" ); document.write( "\"log%2810%2C2%29+=+.301029996\"
\n" ); document.write( "so:
\n" ); document.write( "\"log%282%2C8%29+=+log%2810%2C8%29%2Flog%2810%2C2%29\"
\n" ); document.write( "becomes:
\n" ); document.write( "\"log%282%2C8%29+=+.903089987+%2F+.301029996\"
\n" ); document.write( "which becomes:
\n" ); document.write( "\"log%282%2C8%29+=+3\"
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\n" ); document.write( "since you already know that \"2%5E3\" = 8
\n" ); document.write( "then:
\n" ); document.write( "\"log%282%2C8%29+=+3\" if and only if \"8+=+2%5E3\"
\n" ); document.write( "is confirmed to be a true statement.
\n" ); document.write( "and:
\n" ); document.write( "\"8+=+2%5E3\" if and only if \"log%282%2C8%29+=+3\"
\n" ); document.write( "is also confirmed to be a true statement.
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\n" ); document.write( "you can start from either one and derive the other.
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