Đáp án:
$\left \{ {{\frac{x}{y}=\frac{2}{3}} \atop {3x-2y=5}} \right.$
⇔$\left \{ {{2x=3y} \atop {3x-2y=5}} \right.$
⇔$\left \{ {{2x-3y=0} \atop {3x-2y=5}} \right.$
⇔$\left \{ {{6x-9y=0} \atop {6x-4y=10}} \right.$
⇔$\left \{ {{6x-9y-6x+4y=-10} \atop {6x-4y=5}} \right.$
⇔$\left \{ {{-5y=-10} \atop {6x-4y=5}} \right.$
⇔$\left \{ {{y=2} \atop {x=3}} \right.$
vậy hpt có nghiệm duy nhất (x;y)=(3;2)
