Question

\(\frac{2}{7}x-\frac{1-x}{3}=\frac{-11}{21}\) 

Tim x

Answer 1

Ta có:

\(\frac{2}{7}x-\frac{1-x}{3}=\frac{-11}{21}\)

\(\frac{2}{7}x-\left(\frac{1}{3}-\frac{1}{3}x\right)=\frac{-11}{21}\)

\(\frac{2}{7}x+\frac{1}{3}x-\frac{1}{3}=-\frac{11}{21}\)

\(\left(\frac{6}{21}+\frac{7}{21}\right)x=-\frac{11}{21}+\frac{7}{21}\)

\(\frac{13}{21}x=-\frac{4}{21}\)

\(x=-\frac{4}{21}:\frac{13}{21}=-\frac{4}{21}.\frac{21}{13}=-\frac{4}{13}\)

Vậy \(x=-\frac{4}{13}\)

Answer 2

\(\frac{2}{7}x-\frac{1-x}{3}=\frac{-11}{21}\Leftrightarrow6x-7+7x=-11\Leftrightarrow13x=-4\Leftrightarrow x=\frac{-4}{13}\)

Answer 3

nhưng mình mới học lớp 6