tớ chỉ làm được phần a)thôi
ta có:\(\left(x-\frac{2}{3}\right):\frac{-3}{7}=\frac{-9}{11}\)
\(x-\frac{2}{3}=\frac{-9}{11}.\frac{-3}{7}\)
\(x-\frac{2}{3}=\frac{27}{77}\)
\(x=\frac{27}{77}+\frac{2}{3}\)
\(x=\frac{235}{231}\)
vậy x=\(\frac{235}{231}\)
a) \(\left(x-\frac{2}{3}\right)\):\(\frac{-3}{7}\)=\(\frac{-9}{1}\)
\(x-\frac{2}{3}\)=\(-9\cdot\frac{-3}{7}\)
\(x-\frac{2}{3}\)= \(\frac{27}{7}\)
\(x\)= \(\frac{27}{7}\)\(+\frac{2}{3}\)
\(x\)=\(\frac{95}{21}\)
b)\(x:2+x:\frac{5}{2}+x:\frac{1}{3}=\frac{-18}{25}\)
\(x:\left(2+\frac{5}{2}+\frac{1}{3}\right)=\frac{-18}{25}\)
\(x:\frac{12+15+2}{6}=\frac{-18}{25}\)
\(x:\frac{29}{6}=\frac{-18}{25}\)
\(x=\frac{-18}{25}\cdot\frac{29}{6}\)
\(x=\frac{-87}{25}\)