<PRE><B>Question 168325</B>
xy-3x+4y-12/ xy+5x+4y+20

[x(y-3) + 4(y-3)] / [x(y+5) + 4(y+5)]

[(x+4)(y-3)] / [(x+4)(y+5)]

Cancel the common x+4 factor to get:

= (y-3)/(y+5)

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xy+6x-3y-18/ xy+5x-3y-15 

[x(y+6) -3(y+6)] / [x(y+5) -3(y+5)]

[(x-3)(y+6)] / [(x-3)(y+5)]

= (y+6)/(y+5)

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Cheers,
Stan H.
</PRE>