4x2 - 4x + 9y2 - 6y + 2 = 0
4x2 - 4x + 9y2 - 6y + 1 + 1 = 0
(4x2 - 4x + 1) + (9y2 - 6y + 1) = 0
(2x - 1)2 + (3y - 1)2 =0
=> (2x - 1)2 = 0 2x - 1 = 0 2x = 1 x = 1/2
<=> <=> <=>
(3y - 1)2 = 0 3y - 1 = 0 3y = 1 y = 1/3
Vậy x = 1/2 và y = 1/3