Question

\(\frac{x}{2}=\frac{y}{3};\frac{y}{4}=\frac{z}{5}\)và x + y - z = 10

Answer 1

theo đề ta  có: \(\frac{x}{2}=\frac{y}{3};\frac{y}{4}=\frac{z}{5}\)

=> \(\frac{x}{8}=\frac{y}{12};\frac{y}{12}=\frac{z}{15}\) => \(\frac{x}{8}=\frac{y}{12}=\frac{z}{15}\) và x + y - z = 10

áp dụng t/c DTSBN ta có:

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

=> \(\hept{\begin{cases}\frac{x}{8}=2=>x=16\\\frac{y}{12}=2=>y=24\\\frac{z}{15}=2=>z=30\end{cases}}\)

ok nha!! 4364564564764756756364564565764574576767653454354456546556

Answer 2

từ \(\frac{x}{2}=\frac{y}{3};\frac{y}{4}=\frac{z}{5}\)    =>  \(\frac{x}{8}=\frac{y}{12}=\frac{z}{15}\) 

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

   =>  x =16  ; y= 24;   z=30