Violympic vong 17

V

vipboycodon

Bài 4:
$5x-2\sqrt{x}(2+y)+y^2+1 = 0$
<=> $4x-4\sqrt{x}+1+x-2y\sqrt{x}+y^2 = 0$
<=> $(2\sqrt{x}-1)^2+(\sqrt{x}-y)^2 = 0$
<=> $x = \dfrac{1}{4}$ , $y = \dfrac{1}{2}$
 
Top Bottom