Find all $3$-tuples of positive reals $(a,b,c)$ such that $$\begin{cases}a\sqrt[2019]b-c=a\\b\sqrt[2019]c-a=b\\c\sqrt[2019]a-b=c\end{cases}$$
Source: IMOC 2019 A3
Tags: algebra, system of equations
Find all $3$-tuples of positive reals $(a,b,c)$ such that $$\begin{cases}a\sqrt[2019]b-c=a\\b\sqrt[2019]c-a=b\\c\sqrt[2019]a-b=c\end{cases}$$