Tìm giá trị x, biết: \(\frac{2}{3}x + \frac{1}{2} = \frac{1}{{10}}\) 

* Hướng dẫn giải

\(\begin{array}{l}\,\frac{2}{3}x + \frac{1}{2} = \frac{1}{{10}}\\\,\,\,\,\frac{2}{3}x\,\,\,\,\,\,\,\,\,\,\, = \frac{1}{{10}} - \frac{1}{2}\\\,\,\,\,\frac{2}{3}x\,\,\,\,\,\,\,\,\,\,\, = \frac{{ - 2}}{5}\\\,\,\,\,\,\,\,\,\,x\,\,\,\,\,\,\,\,\, = \,\frac{{ - 2}}{5}:\frac{2}{3}\\\,\,\,\,\,\,\,\,\,x\,\,\,\,\,\,\,\, = \frac{{ - 3}}{5}\end{array}\)

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