Posted by Jay on .
Add or subtract as indicated.
5x/x+3+28/x390/x^29

algebra 
Reiny,
I think you mean
5x/(x+3) + 28/(x3)  90/(x^2  9)
the LCD is (x+3)(x3) or (x^29)
= ( 5x(x3) + 28(x+3)  90)/(x^29)
= (5x^2  15x + 28x + 84 90)/(x^2  9)
= (5x^2 + 13x  6)/(x^2  9)
= (x+3)(5x2) /( (x+3)(x3) )
= (5x2)/(x3)