document.write( "Question 486610: Appreciate help in solving a problem and checking the answer:\r
\n" ); document.write( "\n" ); document.write( "((6x-3)/x^2-x-12))-((2x-15)/x^2-x-12))\r
\n" ); document.write( "\n" ); 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
\n" ); document.write( "\n" ); document.write( "Thanks much.\r
\n" ); document.write( "\n" ); document.write( "Diane
\n" ); document.write( "

Algebra.Com's Answer #332625 by chessace(471)\"\" \"About 
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.
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