$$\left. \begin{array} { l } { a _ { 1 } \frac { - 6 } { 10 } ( - x + \frac { 2 x } { 5 } ) \lt 4 - ( - 2 x + 4 ) } \end{array} \right.$$
$\left\{\begin{matrix}x>0\text{, }&a_{1}<\frac{50}{9}\\x<0\text{, }&a_{1}>\frac{50}{9}\end{matrix}\right.$
$\left\{\begin{matrix}a_{1}<\frac{50}{9}\text{, }&x>0\\a_{1}>\frac{50}{9}\text{, }&x<0\end{matrix}\right.$
