\[\left\{ \begin{matrix} 7x + 4y = 10 \\ 2x + 3y = 1\ \ \ \\ \end{matrix} \right.\ \]
\[(2; - 1):\]
\[\left\{ \begin{matrix} 7 \cdot 2 + 4 \cdot ( - 1) = 10 \\ 2 \cdot 2 + 3 \cdot ( - 1) = 1\ \ \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} 14 - 4 = 10 \\ 4 - 3 = 1\ \ \ \ \ \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} 10 = 10 \\ 1 = 1\ \ \ \ \ \\ \end{matrix} \right.\ \]
\[Является.\]