a) \(0,5x-\frac{2}{3}x=\frac{7}{12}\)
\(\frac{1}{2}x-\frac{2}{3}x=\frac{7}{12}\)
\(\Rightarrow x\left(\frac{1}{2}-\frac{2}{3}\right)=\frac{7}{12}\)
\(x.\frac{-1}{6}=\frac{7}{12}\)
\(x=\frac{7}{12}:\frac{-1}{6}\)
\(x=\frac{-7}{2}\)
b) \(x:4\frac{1}{3}=-2,5\)
\(x:\frac{13}{3}=\frac{-5}{2}\)
\(x=\frac{-5}{2}.\frac{13}{3}\)
\(x=\frac{-65}{6}\)
c) \(5,5x=\frac{13}{15}=\frac{11}{2}x=\frac{13}{5}\)
\(x=\frac{13}{5}:\frac{11}{2}\)
\(x=\frac{26}{55}\)
d) \(\left(\frac{3x}{7}+1\right):\left(-4\right)=\frac{-1}{28}\)
\(\frac{3x}{7}+1=\frac{-1}{28}.\left(-4\right)\)
\(\frac{3x}{7}+1=\frac{1}{7}\)
\(\frac{3x}{7}=\frac{1}{7}-1\)
\(\frac{3x}{7}=\frac{-6}{7}\)
\(\frac{3x}{7}=\frac{-6}{7}\Rightarrow\frac{3.\left(-2\right)}{7}=\frac{-6}{7}\)
Vậy x = -2
\(0,5x-\frac{2}{3}x=\frac{7}{12}\)\(\)
\(\frac{1}{2}x-\frac{2}{3}x=\frac{7}{12}\)
\(x.\left(\frac{1}{2}-\frac{2}{3}\right)=\frac{7}{12}\)
\(x.\frac{-1}{6}=\frac{7}{12}\)
\(x=\frac{7}{12}:\frac{-1}{6}\)
\(x=3,5\)
