Сокращение дробей

1. a) $$\frac{12a^6b}{27a^2b^3} = \frac{4a^4}{9b^2}$$
2. б) $$\frac{3x^2-15x}{15x} = \frac{3x(x-5)}{15x} = \frac{x-5}{5}$$
3. в) $$\frac{x^2-16}{2x-8} = \frac{(x-4)(x+4)}{2(x-4)} = \frac{x+4}{2}$$