Question

Решите с объяснением,пожалуйста.

Answer 1

${} displaystyle left(3x-frac{3x}{x-4} right) : left(x-frac{6x-25}{x-4} right) = \\\ =frac{3x(x-4)-3x}{x-4} :frac{x(x-4)-(6x-25)}{x-4} = \\\ =frac{3x^2-12x-3x}{x-4} :frac{x^2-4x-6x+25}{x-4} = \\\ = frac{3x^2-15x}{x-4} :frac{x^2-10x+25}{x-4}= frac{3x(x-5)}{x-4} :frac{(x-5)^2}{x-4}= \\\ =frac{3x(x-5)}{x-4} cdot frac{x-4}{(x-5)^2}= frac{3x}{x-5}$

Answer 2

$Big (3x-frac{3x}{x-4}Big ):Big (x-frac{6x-25}{x-4}Big )=\\=frac{3x^2-12x-3x}{x-4}:frac{x^2-4x-6x+25}{x-4}=frac{3x^2-15x}{x-4}cdot frac{x-4}{x^2-10x+25}=\\=frac{3x(x-5)}{(x-5)^2}=frac{3x}{x-5}$