document.write( "Question 277318: My son has 2 problems that seem impossible.\r
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document.write( "(1) 1/(x-1)-(2(3x+1)/5x-2)+1/(1-x)=0\r
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document.write( "(2)(7x+5)/6-(5(x-1))/4=1/3+8/(1-x)\r
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document.write( "Thank you for your help \n" );
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Algebra.Com's Answer #201946 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! Thank you for your prompt reply. We are still not sure how in problem 1 you can modify the equation 1/(x-1)...+ 1/(1-x)to your modification of 1/(x-1)...- 1/(x-1). \n" ); document.write( "------------------------------------ \n" ); document.write( "(1) \n" ); document.write( "1/(x-1)-(2(3x+1)/5x-2)+1/(1-x)=0 \n" ); document.write( "Modify the 3rd term: +1/(1-x) \n" ); document.write( "Multiply numerator and denominator by -1 to get -1/(x-1) \n" ); document.write( "Also apply the distributive law on the 2nd term.\r \n" ); document.write( "\n" ); document.write( "[1/(x-1)] - [(6x+2)/(5x-2)] - [(1/(x-1)] = 0 \n" ); document.write( "--- \n" ); document.write( "Notice that the 1st and 3rd terms add up to zero. \n" ); document.write( "---- \n" ); document.write( "(6x+2)/(5x-2) = 0 \n" ); document.write( "--- \n" ); document.write( "The fraction will be zero when the numerator is zero: \n" ); document.write( "--- \n" ); document.write( "6x+2 = 0 \n" ); document.write( "6x = -2 \n" ); document.write( "x = -2/6 \n" ); document.write( "x = -1/3 \n" ); document.write( "=================================== \n" ); document.write( "The same question arises in problem 2 when you go from ... 1/3 + 8/(1-x) to ...1/3 - 8/(x-1). Perhaps you can explain that. \n" ); document.write( "--- \n" ); document.write( "you have 8/(1-x) \n" ); document.write( "Multiply numerator and denominator by -1 to get: \n" ); document.write( "-8/(x-1)\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(2) \n" ); document.write( "[(7x+5)/6]-[(5(x-1))/4] = [1/3]+[8/(1-x)]\r \n" ); document.write( "\n" ); document.write( "--- \n" ); document.write( "[(7x+5)/6]-[(5(x-1))/4] = [1/3]-[8/(x-1)] \n" ); document.write( "--- \n" ); document.write( "Multiply thru by 12(x-1) to get rid of the denominators: \n" ); document.write( "[2(x-1)(7x+5)] - [15(x-1)^2] = [4(x-1)] - [12*8] \n" ); document.write( "---- \n" ); document.write( "Modify: \n" ); document.write( "[2(7x^2-2x-5] - [15(x^2-2x+1)] = [4x-4]-[96] \n" ); document.write( "--- \n" ); document.write( "14x^2-4x-10-15x^2+30x-15 = 4x-100 \n" ); document.write( "--- \n" ); document.write( "-x^2+26x-15 = 4x-100 \n" ); document.write( "-x^2+22x+85 = 0 \n" ); document.write( "x^2-22x-85 = 0 \n" ); document.write( "Factor: \n" ); document.write( "(x-17)(x-5) = 0 \n" ); document.write( "x = 17 or x = 5 \n" ); document.write( "============================= \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |