Algebra.Com's Answer #810395 by ikleyn(52781)![\"\"](\"/images/stars/stars-13.gif\")  
You can put this solution on YOUR website!
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document.write( "Make a the subject of the formula in the equation s = (n/2)*(2a+(n-1)d).
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document.write( " Please pay attention how I edited your writing to make the formula correct.\r
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document.write( "You start from\r\n" );
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document.write( " s =  .\r\n" );
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document.write( "Multiply both sides by  . You get then\r\n" );
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document.write( "  = 2a + (n-1)d.\r\n" );
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document.write( "Next move the term (n-1)*d from the right side to the left side CHANGING ITS SIGN. You will get then\r\n" );
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document.write( "  = 2a.\r\n" );
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document.write( "Last step multiply both sides by  . You finally get\r\n" );
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document.write( " | a =  . |\r\n" );
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document.write( "It is your answer.\r\n" );
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document.write( "You can transform this final formula further as you wish (using equivalent transformations, ONLY).\r\n" );
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document.write( "Solved and carefully explained.\r
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document.write( "Ignore the post by @mananth, since it is TOTALLY WRONG.\r
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