Question

Мне нужно полное решение

Answer 1

$\frac{x^2}{x^2+9xy}: \frac{x}{x^2-81y^2}= \frac{x^2}{x(x+9y)}: \frac{x}{x^2-(9y)^2}=\\\\= \frac{x^2}{x(x+9y)}: \frac{x}{(x-9y)(x+9y)}= \frac{x^2(x-9y)(x+9y)}{x^2(x+9y)}=x-9y$

$x=7-9 \sqrt{2};\; \; y=5- \sqrt{2}\\\\x-9y=7-9 \sqrt{2}-9(5- \sqrt{2})=7-9 \sqrt{2}-45+9 \sqrt{2}=-38$

Answer 2

$\frac{x^2}{x^2+9xy} : \frac{x}{x^2-81y^2} = \frac{x^2}{x(x+9y)} \cdot \frac{(x-9y)(x+9y)}{x} = x-9y \\ x-9y= 7-9 \sqrt{2} - 9 \cdot (5- \sqrt{2}) = 7-9 \sqrt{2} - 45+ 9\sqrt{2} = -38$