Áp dụng tính chất dãy tỉ số bằng nhau:
$⇒\dfrac{x}{2}+\dfrac{y}{3}=\dfrac{x+y}{2+3}=\dfrac{x+y}{5}$
\(⇒\left[ \begin{array}{l}\dfrac{x}{2}=\dfrac{x+y}{5}⇒x=\dfrac{2x+2y}{5}\\\dfrac{y}{3}=\dfrac{x+y}{5}⇒y=\dfrac{3x+3y}{5}\end{array} \right.\)
Vậy $(x,y)=(\dfrac{2x+2y}{5},\dfrac{3x+3y}{5})$
