Question

x/y=7/20:y/z=5/8 va  2x+5y-2z=100

Answer 1

Ta có: \(\frac{x}{y}=\frac{9}{7};\frac{y}{z}=\frac{5}{8}\Rightarrow\frac{x}{9}=\frac{y}{7};\frac{y}{5}=\frac{z}{8}\Rightarrow\frac{x}{45}=\frac{y}{35}=\frac{z}{56}=\frac{-15}{66}=\frac{-5}{22}\)

\(\Rightarrow\frac{x}{45}=\frac{-5}{22}\Rightarrow x=\frac{-225}{22};\frac{y}{35}=\frac{-5}{22}\Rightarrow y=\frac{-175}{22};\frac{z}{56}=\frac{-5}{22}\Rightarrow z=\frac{-140}{11}\)