Ответ:\(\frac{25a^2b^3}{60a^3b}=\frac{5b^2}{12a}\), при \(a\ne0,\ b\ne0\).\(\frac{4x}{3x^2-2x}=\frac{4x}{x(3x-2)}=\frac{4}{3x-2}\), при \(x\ne0,\ x\ne\frac23\).\(\frac{y^2-49}{14-2y}=\frac{(y-7)(y+7)}{2(7-y)}=-\frac{y+7}{2}\), при \(y\ne7\).