Помогите с системой {Х+У=2 внизу {ХУ=-15

X + y = 2

xy = - 15

x = 2 - y

(2 - y) y + 15 = 0 *

- y^2 + 2y + 15 = 0 / : (-1)

y^2 - 2y - 15 = 0

D = 4 + 60 = 64

y1 = (2 + 8) / 2 = 10/2 = 5

y2 = (2 - 8) / 2 = - 6/2 = - 3

x1 = 2 - y1 = 2 - 5 = - 3

y1 = 5

x2 = 2 - y2 = 2 + 3 = 5

y2 = - 3

Ответ

(- 3; 5) ; (5; - 3)