Đáp án:
d) \(\dfrac{7}{{27}} \ge x\)
Giải thích các bước giải:
\(\begin{array}{l}
a)\dfrac{{7 - 3x}}{4} = \dfrac{{5 - 2x}}{1}\\
\to 7 - 3x = 20 - 8x\\
\to 5x = 13\\
\to x = \dfrac{{13}}{5}\\
b)\dfrac{{x - 3}}{5} - \dfrac{{7x + 1}}{2} < \dfrac{{x + 5}}{{10}}\\
\to \dfrac{{2x - 6 - 5\left( {7x + 1} \right) - x - 5}}{{10}} < 0\\
\to 2x - 6 - 35x - 5 - x - 5 < 0\\
\to - 34x < 16\\
\to x > - \dfrac{8}{{17}}\\
c)\dfrac{{3x - 2}}{3} + \dfrac{{2 - 7x}}{6} < \dfrac{7}{2}\\
\to \dfrac{{2\left( {3x - 2} \right) + 2 - 7x - 21}}{6} < 0\\
\to 6x - 4 - 7x - 19 < 0\\
\to x > - 23\\
d)\dfrac{{5 - 3x}}{4} - \dfrac{{7x}}{6} \ge \dfrac{{x + 2}}{3}\\
\to \dfrac{{3\left( {5 - 3x} \right) - 2.7x - 4\left( {x + 2} \right)}}{{12}} \ge 0\\
\to 15 - 9x - 14x - 4x - 8 \ge 0\\
\to 7 \ge 27x\\
\to \dfrac{7}{{27}} \ge x
\end{array}\)
