document.write( "Question 253720: If a=log(base7)(11-6√2) and b=log(base7)(45+29√2), find 3a+2b in the simplest form. \n" ); document.write( "
Algebra.Com's Answer #186175 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
If \"a=log%287%2C%2811-6%2Asqrt%282%29%29%29\" and \"b=log%287%2C%2845%2B29%2Asqrt%282%29%29%29\", find 3a+2b in the simplest form.\r
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\n" ); document.write( "\n" ); document.write( "\"a+=+log%287%2C%2811-6%2Asqrt%282%29%29%29\" if and only if \"7%5Ea+=+11-6%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"b+=+log%287%2C%2845%2B29%2Asqrt%282%29%29%29\" if and only if \"7%5Eb+=+45%2B29%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "take log of both sides of first equation to get:\r
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\n" ); document.write( "\n" ); document.write( "\"7%5Ea+=+11-6%2Asqrt%282%29\" becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"log%28%287%5Ea%29%29+=+log%28%2811-6%2Asqrt%282%29%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "this becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"a%2Alog%28%287%29%29+=+log%28%2811-6%2Asqrt%282%29%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "divide both sides by log((7)) to get:\r
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\n" ); document.write( "\n" ); document.write( "\"a+=+log%28%2811-6%2Asqrt%282%29%29%29%2Flog%28%287%29%29\" *************\r
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\n" ); document.write( "\n" ); document.write( "take log of both sides of second equation to get:\r
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\n" ); document.write( "\n" ); document.write( "\"7%5Eb+=+45%2B29%2Asqrt%282%29\" becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"log%28%287%5Eb%29%29+=+log%28%2845+%2B+29%2Asqrt%282%29%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "this becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"b%2Alog%28%287%29%29+=+log%28%2845+%2B+29%2Asqrt%282%29%29%29\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "divide both sides by log((7)) to get:\r
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\n" ); document.write( "\n" ); document.write( "\"b+=+log%28%2845%2B29%2Asqrt%282%29%29%29%2Flog%28%287%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\r
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\n" ); document.write( "\n" ); document.write( "since the denominator is the same, we get:\r
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\n" ); document.write( "\n" ); document.write( "I don't think you can simplify it any further, but you can solve it using the LOG function of your calculator.\r
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\n" ); document.write( "\n" ); document.write( "equation becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"3a+%2B+2b+=+%283%2A.400489398+%2B+2%2A1.934560022%29%2F.84509804\"\r
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\n" ); document.write( "\n" ); document.write( "this becomes:\r
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\n" ); document.write( "\n" ); document.write( "\"3a+%2B+2b+=+%281.201468195+%2B+3.869120045%29%2F.84509804+=+6\"\r
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\n" ); document.write( "\n" ); document.write( "I confirmed the answer is correct by using the logarithm base conversion formula to convert base 7 logarithm to a base 10 logarithm.\r
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\n" ); document.write( "\n" ); document.write( "that conversion formula is:\r
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\n" ); document.write( "\n" ); document.write( "\"log%287%2C%28x%29%29+=+log%2810%2C%28x%29%29%2Flog%2810%2C%287%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "you could also have solved this problem directly by using the base conversion formula.
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