_4y_____ _ ___3y________
write the q again
As you can see from the appearance above it, it is very hard to line up fractions in this format.
However, your presentation is much better than what we normally encounter.
4y/(y^2 + 6y + 5) - 3y/(y^2 + 5y + 4)
= 4y/((y+1)(y+5)) - 3y/((y+1)(y+4))
= (4y(y+4) - 3y(y+5))/((y+1)(y+4)(y+5))
= (4y^2 + 16 - 3y^2 - 15)/((y+1)(y+4)(y+5))
= (y^2 + 1)/((y+1)(y+4)(y+5))