Đáp án:
m=-1
Giải thích các bước giải:
\(\begin{array}{l}
\left\{ \begin{array}{l}
2x + y = 5m + 5{\rm{ }}\\
x + 2y = 4m + 4\\
y = \frac{1}{5}x
\end{array} \right. \to \left\{ \begin{array}{l}
2x + \frac{1}{5}x = 5m + 5\\
x + \frac{2}{5}x = 4m + 4\\
y = \frac{1}{5}x
\end{array} \right.\\
\to \left\{ \begin{array}{l}
y = \frac{1}{5}x\\
\frac{{11}}{5}x = 5m + 5\\
\frac{7}{5}x = 4m + 4
\end{array} \right. \to \left\{ \begin{array}{l}
y = \frac{1}{5}x\\
x = 0\\
m = - 1
\end{array} \right.\\
\to m = - 1
\end{array}\)