Ta có: \(\frac{-3}{4}=\frac{-6}{x}\Rightarrow x=\frac{4.\left(-6\right)}{-3}=8\)
Thế x = 8 \(\Rightarrow\frac{-6}{8}=\frac{y}{20}\Rightarrow y=\frac{\left(-6\right).20}{8}=-15\)
Thế y = -15 \(\Rightarrow\frac{-15}{20}=\frac{-15}{z}\Rightarrow z=\frac{20.\left(-15\right)}{-15}=20\)
Vậy x = 8 ; y = -15 ; z = 20