Question 73003
find the difference in simplest form. 
((5)/(x+5))) - ((2x+5)/(x^(2)+9x+20))) 

Factor the 2nd denominator as: (x+4)(x+5)
Then the lcd (least common denominator is (x+4)(x+5)
Write each fraction with the lcd as its denominator:
[5(x+4)]/lcd - [(2x+5)]/lcd

Since the denominators are the same, combine the numerators to get:

[5x+20-2x-5]/lcd
(3x+15)/lcd
(3(x+5))/[(x+4)(x+5)]
Cancel the common factor of (x+5) to get:
3/(x+4)

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Cheers,
Stan H.