Ta có: \(\frac{x-4}{y-3}=\frac{4}{3}\)
\(\Rightarrow\left(x-4\right)3=\left(y-3\right)4\)
\(\Rightarrow3x-12=4y-12\)
\(\Rightarrow3x-4y=0\)
\(\Rightarrow3x=4y\)
\(\Rightarrow\frac{x}{4}=\frac{y}{3}\)
Áp dụng t/c dãy tỉ số bằng nhau ta có:
\(\frac{x}{4}=\frac{y}{3}=\frac{x-y}{4-3}=5\)
Do \(\left[\begin{matrix}\frac{x}{4}=5\\\frac{y}{3}=5\end{matrix}\right.\)
\(\Rightarrow\left[\begin{matrix}x=20\\y=15\end{matrix}\right.\)
Vậy \(\left[\begin{matrix}x=20\\y=15\end{matrix}\right.\).
Ta có: \(\frac{x-4}{y-3}=\frac{4}{3}\)
\(\Rightarrow3\left(x-4\right)=4\left(y-3\right)\)
\(\Rightarrow3x-12=4y-12\)
\(\Rightarrow3x-4y=0\)
\(\Rightarrow3x-3y-y=0\)
\(\Rightarrow3\left(x-y\right)-y=0\)
Thay \(x-y=5\)
\(\Rightarrow3.5-y=0\)
\(\Rightarrow15-y=0\)
\(\Rightarrow y=15\)
\(\Rightarrow x-15=5\)
\(\Rightarrow x=15+5\)
\(\Rightarrow x=20\)
Vậy .....
