Giải thích các bước giải:
Ta có :
$\dfrac{2+3x}{13}=\dfrac{2+6y}{17}$
$\to 17(2+3x)=13(2+6y)$
$\to 34+51x=26+78y$
$\to y=\dfrac{51x+18}{78}$
Lại có :
$\dfrac{2+3x}{13}=\dfrac{2+9y}{8x}$
$\to 8x(2+3x)=13(2+9y)$
$\to 16x+24x^2=26+117y$
$\to 16x+24x^2=26+117.\dfrac{51x+18}{78}$
$\to 24x^2-\dfrac{121x}{2}-53=0$
$\to x=\dfrac{121+\sqrt{34993}}{96},\:x=\dfrac{121-\sqrt{34993}}{96}$
$\to y$
