\(\dfrac{x-1}{2017}=\dfrac{3-y}{2018}\)
Áp dụng t/c của dãy tỉ số bằng nhau, ta có:
\(\dfrac{x-1}{2017}=\dfrac{3-y}{2018}=\dfrac{x-1+3-y}{2017+2018}=\dfrac{x-y+2}{4035}=\dfrac{4035+2}{4035}=\dfrac{4037}{4035}\)
\(\Rightarrow\left\{{}\begin{matrix}x-1=\dfrac{4037}{4035}\cdot2017\\3-y=\dfrac{4037}{4035}\cdot2018\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x-1=\dfrac{8142629}{4035}\\3-y=\dfrac{8146666}{4035}\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=\dfrac{8146664}{4035}\\y=-\dfrac{8134561}{4035}\end{matrix}\right.\)
\(\dfrac{x-1}{2017}=\dfrac{3-y}{2018}\\ \Rightarrow\dfrac{x-1}{2017}=\dfrac{3-y}{2018}=\dfrac{x-1+3-y}{2017+2018}\\ =\dfrac{x-y+2}{4035}\\ =\dfrac{4033}{4035}\)
