Question

Giúp em câu 4 với ạ

Answer 1

Áp dụng t/c dtsbn:
\(\dfrac{x}{3}=\dfrac{y}{5}=\dfrac{z}{-2}=\dfrac{5x}{15}=\dfrac{3z}{-6}=\dfrac{5x+y+3z}{15+5-6}=\dfrac{12}{14}=\dfrac{6}{7}\)

\(\Rightarrow\left\{{}\begin{matrix}x=\dfrac{6}{7}.3=\dfrac{18}{7}\\y=\dfrac{6}{7}.5=\dfrac{30}{7}\\z=\dfrac{6}{7}.\left(-2\right)=-\dfrac{12}{7}\end{matrix}\right.\)