$|5x-3|-x=7$
$⇔|5x-3|=7+x$
$⇔\left[ \begin{array}{l}5x-3=7+x\\5x-3=-(7+x)\end{array} \right.$
$⇔\left[ \begin{array}{l}5x-x=7+3\\5x-3=-7-x\end{array} \right.$
$⇔\left[ \begin{array}{l}4x=10\\5x+x=-7+3\end{array} \right.$
$⇔\left[ \begin{array}{l}x=\frac{5}{2}\\6x=-4\end{array} \right.$
$⇔\left[ \begin{array}{l}x=\frac{5}{2}\\x=\frac{-2}{3}\end{array} \right.$
Vậy $x∈{\frac{5}{2};\frac{-2}{3}}$
Ta có: $2x=3y=5z$
$⇒\frac{2x}{30}=\frac{3y}{30}=\frac{5z}{30}$
$⇒\frac{x}{15}=\frac{y}{10}=\frac{z}{6}$
Áp dụng tính chất dãy tỉ số bằng nhau, ta có:
$\frac{x}{15}=\frac{y}{10}=\frac{z}{6}=\frac{x+y-z}{15+10-6}=\frac{95}{19}=5$
$\frac{x}{15}=5⇒x=5,15=75$
$\frac{y}{10}=5⇒y=5.10=50$
$\frac{z}{6}=5⇒z=5.6=30$
Vậy $x=75; y = 50; z = 30$
