document.write( "Question 486610: Appreciate help in solving a problem and checking the answer:\r
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document.write( "((6x-3)/x^2-x-12))-((2x-15)/x^2-x-12))\r
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document.write( "The answer I got is 4/(x-4) but not sure if this is correct and don't know how to check.\r
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document.write( "Thanks much.\r
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document.write( "Diane \n" );
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Algebra.Com's Answer #332625 by chessace(471) You can put this solution on YOUR website! Since () are used somewhat, assume (1st) this problem is \n" ); document.write( "((6x-3)/x^2)-x-12-((2x-15)/x^2)-x-12 rather than \n" ); document.write( "(2nd) (6x-3)/(x^2-x-12)-(2x-15)/(x^2-x-12). \n" ); document.write( "Maybe it was clear in original form. \n" ); document.write( "(1st): \n" ); document.write( "((6x-3)/x^2)-x-12-((2x-15)/x^2)-x-12 \n" ); document.write( "= ((6x-3-2x+15)/x^2)-x-12-x-12 \n" ); document.write( "= ((4x+12)/x^2) -2(4x+12) not looking good! \n" ); document.write( "(2nd): \n" ); document.write( "(6x-3)/(x^2-x-12)-(2x-15)/(x^2-x-12) \n" ); document.write( "= (6x-3-2x+15)/(x^2-x-12) \n" ); document.write( "= (4x+12)/((x+3)(x-4)) \n" ); document.write( "= 4/(x-4) \n" ); document.write( "Much better, and matches yours. \n" ); document.write( "As for checking any answer, one quick test is to set x=0 then x=1 and see if results are same: \n" ); document.write( "x=0: -3/(-12)-(-15)/(-12)= 1/4-5/4 = -1 v. -1 OK! \n" ); document.write( "x=1: (3/-12)-(-13)/(-12) = -1/4 - 13/12 v. 4/(-3) \n" ); document.write( "(-3/12)-13/12 v. -16/12 OK! \n" ); document.write( "A 3rd point, say x=-1 would cinch it, but 2 is plenty. \n" ); document.write( " \n" ); document.write( " |