Решить систему уравнений { (x^2-8xy+16y^2=4, xy+4y^2=6)

{x² - 8 x y + 16 y² = 4; { (x - 4 y) ² = 4; { (x - 4 y) ² = 4; { (x - 4 y) ² = 4;

{x y + 4 y² = 6; {y (x + 4 y) = 6; {x + 4 y = 6 / y; {x = 6 / y - 4 y;

(6 / y - 4 y - 4 y) ² = 4; (6 / y - 8 y) ² = 4; 4 (3 / y - 4 y) ² = 4; (3 / y - 4 y) ² = 1;

9/y² - 24 + 16 y² = 1; 9 - 24 y² + 16 y^4 = y²;

16 y^4 - 25 y² + 9 = 0; y² = z;

16 z² - 25 z + 9 = 0; D = 625 - 576 = 49;

z = (25 ± √49) : 32;

z = (25 + 7) : 32; z = 1;

z' = (25 - 7) : 32; z' = 9/16;

y = √1; y = 1; y' = - 1;

y = √ (9/16); y'' = 3/4; y''' = - 3/4;

x = 6 : 1 - 4 * 1; x = 2;

x' = 6 : ( - 1) - 4 * ( - 1); x' = - 2;

x'' = 6 : 3/4 - 4 * 3/4; x'' = 5;

x''' = 6 : ( - 3/4) - 4 * ( - 3/4); x''' = - 5;

{x = 2; y = 1; {x = - 2; y = - 1; {x = 5; y = 3/4; (x = - 5; y = - 3/4.