Đáp án:
1) \(x < - \dfrac{{47}}{{21}}\)
Giải thích các bước giải:
\(\begin{array}{l}
1)\left\{ \begin{array}{l}
3x + \dfrac{4}{7} < 2x - \dfrac{5}{3}\\
x + \dfrac{4}{3} > 9x - 8
\end{array} \right.\\
\to \left\{ \begin{array}{l}
x < - \dfrac{{47}}{{21}}\\
8x < \dfrac{{28}}{3}
\end{array} \right.\\
\to \left\{ \begin{array}{l}
x < - \dfrac{{47}}{{21}}\\
x < \dfrac{7}{6}
\end{array} \right.\\
\to x < - \dfrac{{47}}{{21}}\\
2)\left\{ \begin{array}{l}
\dfrac{{5\left( {3x + 7} \right) - 2\left( {4x - 3} \right) - 4.10}}{{10}} < 0\\
\dfrac{{3\left( {5x - 3} \right) - x - 7 + 2.3}}{3} > 0
\end{array} \right.\\
\to \left\{ \begin{array}{l}
5\left( {3x + 7} \right) - 2\left( {4x - 3} \right) - 4.10 < 0\\
3\left( {5x - 3} \right) - x - 7 + 2.3 > 0
\end{array} \right.\\
\to \left\{ \begin{array}{l}
15x + 35 - 8x + 6 - 40 < 0\\
15x - 9 - x - 1 > 0
\end{array} \right.\\
\to \left\{ \begin{array}{l}
7x < - 1\\
14x > 10
\end{array} \right.\\
\to \left\{ \begin{array}{l}
x < - \dfrac{1}{7}\\
x > \dfrac{5}{7}
\end{array} \right.\left( {vô lý} \right)\\
\to x \in \emptyset
\end{array}\)
