Tìm x, biết x + 2/3 = -4/5
a) \(x + \frac{2}{3} = \frac{{ - 4}}{5}\) \(x = \frac{{ - 4}}{5} - \frac{2}{3}\) \(x = \frac{{ - 22}}{{15}}\) Vậy \(x = \frac{{ - 22}}{{15}}\) | b) \(\frac{{ - 3}}{4} + \frac{1}{3} \cdot x = \frac{1}{6}\) \(\frac{1}{3} \cdot x = \frac{1}{6} + \frac{3}{4}\) \(\frac{1}{3} \cdot x = \frac{{11}}{{12}}\) \(x = \frac{{11}}{4}\) Vậy \(x = \frac{{11}}{4}\) | c) \(\frac{7}{{12}} - \left( {x + \frac{1}{6}} \right) \cdot \frac{6}{5} = {\left( {\frac{{ - 1}}{2}} \right)^3}\) \[\frac{7}{{12}} - \left( {x + \frac{1}{6}} \right) \cdot \frac{5}{6} = \frac{{ - 1}}{8}\] \[\left( {x + \frac{1}{6}} \right) \cdot \frac{5}{6} = \frac{7}{{12}} - \frac{{ - 1}}{8}\] \[\left( {x + \frac{1}{6}} \right) \cdot \frac{5}{6} = \frac{{17}}{{24}}\] \[x + \frac{1}{6} = \frac{{17}}{{24}}:\frac{5}{6}\] \[x + \frac{1}{6} = \frac{{17}}{{20}}\] \[x = \frac{{17}}{{20}} - \frac{1}{6}\] \[x = \frac{{41}}{{60}}\] Vậy \[x = \frac{{41}}{{60}}\] |