\(x+30\%x=-1,3\)
\(\Leftrightarrow x+\frac{30}{100}x=-\frac{13}{10}\)
\(\Leftrightarrow x+\frac{3}{10}x=-\frac{13}{10}\)
\(\Leftrightarrow\left(\frac{3}{10}+1\right)x=-\frac{13}{10}\)
\(\frac{\Leftrightarrow13}{10}x=-\frac{13}{10}\)
\(\Leftrightarrow x=-\frac{13}{10}:\frac{13}{10}\)
\(\Leftrightarrow x=-1\)
Nhớ ấn đúng cko mình nghen :)