((5x+10)(/x-1))*((x²-1)/(x²-4))=(5(x+2)(x-1)(x+1)/((x-1)(x-2)(x+2))=5(x+1)/(x-2).
(24b²c/3a²)/(16bc/a²)=(24b²c*a²)/(3a²*16bc)=24a²b²c/(48a²bc)=b/2.
((y+c)/c)*(c/y-c/(y+c))=((y+c)/c)*((cy+c²-cy)/(y(y+c))=((y+c)/c)*(c²/(y(y+c))=
=(c²(y+c)/(cy(y+c))=c/y.