document.write( "Question 691014: What am I doing wrong here or am I on the right track?\r
\n" ); document.write( "\n" ); document.write( "log5x - log5(x - 2) = log5 4\r
\n" ); document.write( "\n" ); document.write( "log5x - log5 (x - 2) = log5/log4\r
\n" ); document.write( "\n" ); document.write( "log5 x-(x-2) = 1.161\r
\n" ); document.write( "\n" ); document.write( "-x^2 + 2x - 1.161 = 0\r
\n" ); document.write( "\n" ); document.write( "-b +- sqrt b^2 - 4(a)(c) / 2(a)\r
\n" ); document.write( "\n" ); document.write( "-2 +- sqrt 2^2 - 4(-1)(-1.161) / 2(-1)
\n" ); document.write( "

Algebra.Com's Answer #426470 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
Unfortunately, you are far from the right track, and trouble rendering the notation does not help.
\n" ); document.write( "I believe the problem is \"log%285%2Cx%29+-+log%285%2C%28x+-+2%29%29+=+log%285%2C+4%29\"
\n" ); document.write( "For such a problem, you should know and use the definition and properties of logarithms (see below).
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\n" ); document.write( "THE SOLUTION:
\n" ); document.write( "Using knowledge about logarithms:
\n" ); document.write( "\"log%285%2Cx%29-log%285%2C%28x-2%29%29=log%285%2C4%29\" --> \"log%28x%2F%28x-2%29%29=log%285%2C4%29\" --> \"x%2F%28x-2%29=4\"
\n" ); document.write( "Then,
\n" ); document.write( "\"x%2F%28x-2%29=4\" --> \"%28x%2F%28x-2%29%29%28x-2%29=4%28x-2%29\" --> \"x=4x-8\" --> \"x-x=4x-8-x\" --> \"0=3x-8\"
\n" ); document.write( "\"3x-8=0\" --> \"3x-8%2B8=0%2B8\" --> \"3x=8\" --> \"3x%2F3=8%2F3\" --> \"highlight%28x=8%2F3%29\"
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\n" ); document.write( "DEFINITION:
\n" ); document.write( "Logarithm of a number is defined (in down to earth terms) as the exponent you need to put on the base to get that number.
\n" ); document.write( "\"log%285%2C25%29=2\" and \"log%285%2C125%29=3\"
\n" ); document.write( "because \"25=5%5E2\" and \"125=5%5E3\"
\n" ); document.write( "\"log%285%2C4%29\" is not such a simple number.
\n" ); document.write( "You cannot write its exact value as a fraction or a decimal, but it's approximately 0.8614.
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\n" ); document.write( "PROPERTTIES OF LOGARITHMS:
\n" ); document.write( "Some teachers may give you formulas for the properties of logarithms and expect you to remember them.
\n" ); document.write( "However, it is easy to remember (or rediscover) most of those properties by thinking from the definition of logarithm.
\n" ); document.write( "SUM OF LOGARITHMS:
\n" ); document.write( "When using the same base, multiplying powers means adding the exponents
\n" ); document.write( "(example \"%28x%5E4%29%28x%5E5%29=x%5E9\").
\n" ); document.write( "So, when logarithms of the same base are added, you get the logarithm of the product.
\n" ); document.write( "\"log%28b%2Cx%29%2Blog%28b%2Cy%29=log%28b%2Cxy%29\"
\n" ); document.write( "DIFFERENCE OF LOGARITHMS:
\n" ); document.write( "Similarly, subtracting logarithms of the same base gives you the logarithm of the quotient.
\n" ); document.write( "\"log%28b%2Cx%29-log%28b%2Cy%29=log%28b%2Cx%2Fy%29\"
\n" ); document.write( "CHANGE OF BASE:
\n" ); document.write( "That is not quite so obvious.
\n" ); document.write( "To calculate the approximate value of the logarithm of a number in a strange base (like 5), you divide the base 10 logarithms of the number by the base 10 logarithms of the strange base.
\n" ); document.write( "\"log%28b%2Cx%29=log%2810%2Cx%29%2Flog%2810%2Cb%29\"
\n" ); document.write( "So \"log%285%2C4%29=log%2810%2C4%29%2Flog%2810%2C5%29\"
\n" ); document.write( "and since the base can be omitted is it is \"10\", you can write it as
\n" ); document.write( "\"log%285%2C4%29=log%284%29%2Flog%285%29\"
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