document.write( "Question 203500: can someone help me with this question
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document.write( "thanx.\r
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document.write( "solve the following equation for x, giving the answer correct to two decimal places\r
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document.write( "this question is from the book Longman Pre-U Text STPM Mathematics S & T Paper 1
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Algebra.Com's Answer #153526 by jsmallt9(3758) ![]() You can put this solution on YOUR website! To solve for x when it is in exponents is to use logarithms. Since we want our answer in decimal form (and not logarithm form) we need to use a logarithm we can get from out calculator (or other computing device). If calculators have any logarithms at all they will most likely have base 10 logarithms and/or natural (base e) logarithms. Either will work and give the correct answer to the problem. \n" ); document.write( " \n" ); document.write( "Find the log of both sides: \n" ); document.write( " \n" ); document.write( "Now we can get x out of the exponents by using the following property of logarithms (which applies to all bases): \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "We are now in a position to solve for x. We can either
\n" ); document.write( "I will use the second approach. But if you can't understand this, then repalce the logarithm's now and finish the solution using the decimals. \n" ); document.write( "Subtract \n" ); document.write( " \n" ); document.write( "Add \n" ); document.write( " \n" ); document.write( "Divide both sides by \n" ); document.write( " \n" ); document.write( "We can get the logarithms above from our calculator: \n" ); document.write( " \n" ); document.write( "Simplifying gives: \n" ); document.write( " \n" ); document.write( "Rounded to 2 decimal places: \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |