Question

Tìm ba số x, y, z, biết rằng:

      \(\dfrac{x}{2}=\dfrac{y}{3},\dfrac{y}{4}=\dfrac{z}{5}\) với x + y - z = 10

Giúp mk với, 23h58 là mk phải nộp ròi

Answer 1

\(\dfrac{x}{2}=\dfrac{y}{3}\Rightarrow\dfrac{x}{8}=\dfrac{y}{12}\)

\(\dfrac{y}{4}=\dfrac{z}{5}\Rightarrow\dfrac{y}{12}=\dfrac{z}{15}\)

\(\Rightarrow\dfrac{x}{8}=\dfrac{y}{12}=\dfrac{z}{15}=\dfrac{x+y-z}{8+12-15}=\dfrac{10}{5}=2\)

\(\Rightarrow\left\{{}\begin{matrix}x=2.8=16\\y=2.12=24\\z=2.15=30\end{matrix}\right.\)