1/3x-2/5(x+1)=0
1/3x-2/5x-2/5=0
-1/15x-2/5=0
-1/15x=6/15
x=-6
\(A=\frac{1}{3}.x-\frac{2}{5}.\left(x+1\right)=\)\(0\)
\(A=\frac{1}{3}.x-\frac{2}{5}x-\frac{2}{5}\)\(=0\)
\(A=x.\left(\frac{1}{3}-\frac{2}{5}\right)-\frac{2}{5}\)\(=0\)
\(A=x.\frac{-1}{15}=\frac{2}{5}\)
\(A=\frac{2}{5}\div\frac{-1}{15}\)
\(A=-6\)
Vậy \(A=-6\)
\(A=\frac{1}{3}x-\frac{2}{5}\left(x+1\right)=0\)
\(\frac{1}{3}x-\frac{2}{5}x-\frac{2}{5}=0\)
\(-\frac{1}{15}x=\frac{2}{5}\Leftrightarrow A=-6\)