Question

$left { {{x-y=7} atop {x^2-2y=13}} right.$
способом подстановки решите систему уравнений

Answer 1

$left { {{x-y=7} atop {x^2-2y=13}} right. \ left { {{x=7+y} atop {x^2-2y=13}} right. \ (7+y)^2-2y=13 \ 49+14y+y^2-2y=13 \ y=-6 \ x=7-6 \ x=1 \ x=1$
y=-6