nhan $24y$ vao pt duoi roi binh phuong ta co$9x^4-96x^3y+184x^2y^2+384xy^3+144y^4=0$
lai cho cho $x^2y^2\neq0$ ta co
$9(\frac{x^2}{y^2}+\frac{16y^2}{x^2})-96(\frac xy-4\frac yx)+184=0$
dat $\frac xy-4\frac yx=t=>9t^2-96t+252=0=>t=6$ hoac $t=\frac{14}3$
$t=6=>x^2-4y^2=6xy=>x=3^+_-\sqrt{13}y$
$t=\frac{14}3=>3x^2-12y^2=14xy=>x=\frac{7^+_-\sqrt{85}}{3}y$
roi sau do rut the.............