document.write( "Question 206449: I am studying for the compass exam and I see that others have posted the same question: What is the rational expression when r is not equal to plus or minus 2, r^2-5r+6 / r^2-4. What I don't understand is why r^2-5r+6 factors to [(r-3)(r-2)]...please help! \n" ); document.write( "

Algebra.Com's Answer #156000 by RAY100(1637) $\"\"$ $\"About$

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r^2 -5r +6
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\n" ); document.write( "Remember factoring is reverse FOIL
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\n" ); document.write( "factors of first term are only 1*1,,,,,(x,,,,)(x,,,,,)
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\n" ); document.write( "sign of last term is plus, therefore both terms of factor must be the same,,,and the sign of the middle term is negative, therefore both factors have negative,,,,,that is ( x-,,)(x-,,)
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\n" ); document.write( "factors of last term can be,,6*1,,3*2,,,,but which adds to 5 which is middle term,,,must be 3*2,,
\n" ); document.write( "Therefore,,,,(x-3)(x-2) are the factors of x^2 -5x +6
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\n" ); document.write( "to check use FOIL, (x-3)(x-2) = x^2 -2x -3x +6 = x^2 -5x +6 \n" ); document.write( "

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