Question

Решить систему методом алгеабрагического сложения: x^2-2y^2=14 x^2+2y^2=18

Answer 1

$\left \{ {{x^2-2y^2=14,} \atop {x^2+2y^2=18;}} \right. \\ 2x^2=32, \\ x^2=16, \\ \left [ {{x=-4, \atop {x=4;}} \right. \\ \left \{ {{-x^2+2y^2=-14,} \atop {x^2+2y^2=18;}} \right. \\ 4y^2=4, \\ y^2=1, \\ \left [ {{y=-1, \atop {y=1;}} \right. \\ (-4;-1), (-4;1), (4;-1), (4;1).$