PT(1) [tex]10x+15y+10=17(xy+2x-2y-4)[/tex]
PT(2) [tex]6x+3y-30=7(xy+2x-2y-4)[/tex]
[tex]\frac{(1)}{(2)}=\frac{10x+15y+10}{6x+3y-30}=\frac{17}{7}<=>32x-54y-580=0=>x=\frac{27y+290}{16}[/tex]
thay vào (2) [tex]\frac{2}{\frac{27y+290}{16}-1}-\frac{3}{y-1}=\frac{7}{5}[/tex]
=> [tex]y=\frac{-47}{9}-\frac{\sqrt{1201}}{9}=>x=\frac{27\left ( \frac{-47}{9}-\frac{\sqrt{1201}}{9} \right )+290}{16}=\frac{149}{16} - \frac{3 \sqrt{1201}}{16}[/tex]
hoặc [tex]y=\frac{-47}{9}+\frac{\sqrt{1201}}{9}=> x=\frac{27\left ( \frac{-47}{9}+\frac{\sqrt{1201}}{9} \right )+290}{16}=\frac{149}{16}+\frac{3\sqrt{1201}}{16}[/tex]