Solve the differential equation - `(x-2y)dx+(2x+y)dy=0`

Explanation

$$ \begin{aligned} (2 x+y) d y &=-(x-2 y) d x, \\ \frac{d y}{d x} &=\frac{(-x+2 y) \div x}{(2 x+y) \div x} \\ \frac{d y}{d x} &=\frac{-1+2\left(\frac{y}{x}\right)}{2+\left(\frac{y}{x}\right)} \end{aligned} $$
It is a homogeneous equation.
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