6) а) $$rac{x(a+3)}{y(a+3)}$$ б) $$rac{3(x+5)^2}{(x+5)^3}$$ в) $$rac{3a(b-2)}{6(b-2)^2}$$ г) $$rac{x^2(x-8)^3}{x^4(x-8)^2}$$ д) $$rac{3a+3b}{5(a+b)}$$ е) $$rac{7x-14y}{3x-6y}$$

6) а) $$rac{x(a+3)}{y(a+3)} = \frac{x}{y}$$ б) $$rac{3(x+5)^2}{(x+5)^3} = \frac{3}{x+5}$$ в) $$rac{3a(b-2)}{6(b-2)^2} = \frac{a}{2(b-2)}$$ г) $$rac{x^2(x-8)^3}{x^4(x-8)^2} = \frac{x-8}{x^2}$$ д) $$rac{3a+3b}{5(a+b)} = \frac{3(a+b)}{5(a+b)} = \frac{3}{5}$$ е) $$rac{7x-14y}{3x-6y} = \frac{7(x-2y)}{3(x-2y)} = \frac{7}{3}$$