-1,279

theo mik thì: 1/7:x=3/14-3/7

\(\dfrac{3}{7}+\dfrac{1}{7}:x=\dfrac{3}{14}\\ =>\dfrac{1}{7}:x=\dfrac{3}{14}-\dfrac{3}{7}=-\dfrac{3}{14}\\ =>x=\dfrac{1}{7}:\left(-\dfrac{3}{14}\right)\\ =>x=-\dfrac{2}{3}\)

\(\dfrac{1}{3}x+\dfrac{2}{5}\left(x-1\right)=0\\ =>\dfrac{1}{3}x+\dfrac{2}{5}x-\dfrac{2}{5}=0\\ =>\dfrac{11}{15}x=\dfrac{2}{5}\\ =>x=\dfrac{2}{5}:\dfrac{11}{15}\\ =>x=\dfrac{6}{11}\)

\(x-\dfrac{1}{2}=3\dfrac{1}{2}:\dfrac{2}{7}=\dfrac{7}{2}\times\dfrac{7}{2}\\ =>x-\dfrac{1}{2}=\dfrac{49}{4}\\ =>x=\dfrac{49}{4}+\dfrac{1}{2}\\ =>x=\dfrac{51}{4}\)

\(\dfrac{5}{7}+\dfrac{2}{7}:x=\)1

         \(\dfrac{2}{7}:x=1-\) \(\dfrac{5}{7}\)

          \(\dfrac{2}{7}\) : x  = \(\dfrac{2}{7}\)

                x  = \(\dfrac{2}{7}:\dfrac{2}{7}\)

                x = 1

\(3x-\dfrac{5}{3}=x-\dfrac{1}{4}\\ =>3x-x=\dfrac{5}{3}-\dfrac{1}{4}\\ =>2x=\dfrac{17}{12}\\ =>x=\dfrac{17}{24}\)

\(x\cdot\left(-\dfrac{3}{7}\right)=\dfrac{5}{21}\)

\(x=\dfrac{5}{21}:\left(-\dfrac{3}{7}\right)=\dfrac{5}{21}\times\left(-\dfrac{7}{3}\right)\)

\(x=-\dfrac{5}{9}\)

0,(1) = 1/9

0.(01) = 1/99

1,(8) = 17/9

0,27 = 3/11