document.write( "Question 860328: Have reason to believe an error somewhere in my following steps...\r
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document.write( "Original problem: 1/x + 2/(x+2) = 17/35 \r
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document.write( "Using LCD to clear fractions, I get:\r
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document.write( "35x + 70 + 70x = 17x^2 + 34\r
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document.write( "Rewriting to standard quadratic form: \r
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document.write( "17x^2 -105x -36 = 0 \r
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document.write( "Factoring by grouping I get:\r
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document.write( "17x^2 -18x +34x -36
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document.write( "(17x^2 +34x) +(-18x -36)
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document.write( "17x(x+2) -18(x+2)
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document.write( "(17x-18)(x+2)= 0 \r
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document.write( "However, when I FOIL last expression above, I get:
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document.write( "17x^2 +16x -36 ???\r
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document.write( "Shouldn't FOIL result in expression I had above for standard quadratic form -- 17x^2 -105x -36 =0 ?\r
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document.write( "Thanks much
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document.write( "
Algebra.Com's Answer #518315 by mananth(16946)![]() ![]() You can put this solution on YOUR website! \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "LCD = 35x(x+2)\r \n" ); document.write( "\n" ); document.write( "35(x+2)+2*35*x = 17x(x+2)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "35x+70+70x=17x^2+34x\r \n" ); document.write( "\n" ); document.write( "17x^2-71x-70=0\r \n" ); document.write( "\n" ); document.write( "solve for x\r \n" ); document.write( "\n" ); document.write( "you will get x= 5 or -0.82\r \n" ); document.write( "\n" ); document.write( "plug the values in the equation to check\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |