X = y + 3
xy - y = 7
x = y + 3
(y + 3)*y - y = 7
y^2 + 3y - y - 7 = 0
y^2 + 2y - 7 = 0
D = 4 + 4*1*7 = 32
y1 = ( - 2 - 4√2)/2
y1 = - 1 - 2√2
y2 = ( - 2 + 4√2)/2
y2 = - 1 + 2√2
x1 = - 1 - 2√2 + 3
x1 = 2 - 2√2
x2 = - 1 + 2√2 + 3
x2 = 2 + 2√2
Ответ: (2 - 2√2 ; - 1 - 2√2) ; ( 2 + 2√2 ; - 1 + 2√2)