\(\left(\frac{3x}{7}+1\right)\div\left(-4\right)=\frac{-1}{28}\)
\(\frac{3x}{7}+1=\frac{-1}{28}\times\left(-4\right)\)
\(\frac{3x}{7}+1=\frac{1}{7}\)
\(\frac{3x}{7}=\frac{1}{7}-1\)
\(\frac{3x}{7}=\frac{-6}{7}\)
\(3x=\frac{-6}{7}\times7\)
\(3x=-6\)
\(x=-2\)
Vậy x = -2
tớ ko bít đúng hay sai đâu nha
\(\Leftrightarrow\)\(-\frac{1}{28}\cdot\left(-4\right)\)=\(\frac{3x}{7}+1\)
\(\Leftrightarrow\frac{1}{7}=\frac{3x}{7}+1\)
\(\Leftrightarrow\frac{1}{7}-1=3x:7\)
\(\Leftrightarrow3x:7=-\frac{6}{7}\)
\(\Leftrightarrow3x=\frac{-6}{7}.7\)
\(\Leftrightarrow x=-6:3\)
\(\Leftrightarrow x=-2\)