Giải thích các bước giải:
Ta có:
\(\begin{array}{l}
{\left( {7y - x} \right)^{2020}} + {\left| {5 - 11x} \right|^{2021}} = 0\\
{\left( {7y - x} \right)^{2020}} \ge 0,\,\,\,\,\forall x,y\\
\left| {5 - 11x} \right| \ge 0,\,\,\,\,\forall x \Rightarrow {\left| {5 - 11x} \right|^{2021}} \ge 0,\,\,\,\,\forall x\\
\Rightarrow {\left( {7y - x} \right)^{2020}} + {\left| {5 - 11x} \right|^{2021}} \ge 0,\,\,\,\forall x,y\\
\Rightarrow \left\{ \begin{array}{l}
{\left( {7y - x} \right)^{2020}} = 0\\
{\left| {5 - 11x} \right|^{2021}} = 0
\end{array} \right. \Leftrightarrow \left\{ \begin{array}{l}
7y - x = 0\\
5 - 11x = 0
\end{array} \right. \Leftrightarrow \left\{ \begin{array}{l}
x = 7y\\
11x = 5
\end{array} \right. \Leftrightarrow \left\{ \begin{array}{l}
x = \dfrac{5}{{11}}\\
y = \dfrac{{35}}{{11}}
\end{array} \right.
\end{array}\)