a, \(\dfrac{3}{7}\)\(x\) - 0,4 = - \(\dfrac{17}{35}\)
\(\dfrac{3}{7}\)\(x\) = - \(\dfrac{17}{35}\) + 0,4
\(\dfrac{3}{7}\)\(x\) = - \(\dfrac{3}{35}\)
\(x\) = - \(\dfrac{3}{35}\): \(\dfrac{3}{7}\)
\(x\) = - \(\dfrac{1}{5}\)
b, 0,2.(\(x\) - 3) +2,4 = 10
0,2.(\(x\) - 3) = 10 - 2,4
0,2.(\(x\) - 3) = 7,6
\(x\) - 3 = 7,6:0,2
\(x\) - 3 = 38
\(x\) = 38 + 3
\(x\) = 41
\(\dfrac{3}{7}x-0,4=\dfrac{-17}{35}\)
\(\dfrac{3}{7}x=\dfrac{-17}{35}+0,4=\dfrac{-34}{70}+\dfrac{28}{70}\)
\(\dfrac{3}{7}x=\dfrac{-6}{70}=\dfrac{-3}{35}\)
\(x=\dfrac{-3}{35}:\dfrac{3}{7}=\dfrac{-3}{35}\cdot\dfrac{7}{3}\)
\(x=\dfrac{3\cdot\left(-1\right)\cdot7}{5\cdot7\cdot3}=-\dfrac{1}{5}\)
b) \(0,2\left(x-3\right)+2,4=10\)
\(0,2\left(x-3\right)=10-2,4=7,6\)
\(x-3=7,6:0,2=38\)
\(x=38+3=41\)
c) \(\left(x:2,2\right)\cdot\dfrac{1}{6}=\dfrac{-3}{8}\cdot\left(0,5-1\dfrac{3}{5}\right)\)
\(\left(x:2,2\right)\cdot\dfrac{1}{6}=\dfrac{-3}{8}\cdot\dfrac{-11}{10}\)
\(x:2,2=\dfrac{-3}{8}\cdot\dfrac{-11}{10}\cdot\dfrac{6}{1}\)
\(x:2,2=\dfrac{-3\cdot\left(-11\right)\cdot2\cdot3}{2\cdot4\cdot10\cdot1}=\dfrac{99}{40}\)
\(x=\dfrac{99}{40}\cdot2,2=\dfrac{99}{40}\cdot\dfrac{22}{10}\)
\(x=\dfrac{99\cdot2\cdot11}{40\cdot2\cdot5}=\dfrac{1089}{200}\)
c, (\(x\):2,2).\(\dfrac{1}{6}\) = - \(\dfrac{3}{8}\).(0,5 - 1\(\dfrac{3}{5}\))
(\(x\):2,2).\(\dfrac{1}{6}\) = - \(\dfrac{3}{8}\).(-\(\dfrac{11}{10}\))
(\(x\): 2,2) . \(\dfrac{1}{6}\) = \(\dfrac{33}{80}\)
\(x\):2,2 = \(\dfrac{33}{80}\): \(\dfrac{1}{6}\)
\(x\):2,2 = \(\dfrac{99}{40}\)
\(x\) = \(\dfrac{99}{40}\) \(\times\)2,2
\(x\) = \(\dfrac{1089}{200}\)
