Решите систему ,!!!! Зарание спасибо. y-x=-5 x²-2xy-y²=17

Question

Решите систему ,!!!!
Зарание спасибо.
y-x=-5
x²-2xy-y²=17

Answer 1

Y-x= -5 ---- x-y= 5
x^2-2xy-y^2= x^2-2xy+y^2-2y^2=(x-y)^2-2y^2=17
(5)^2-2y^2=17
25-2y^2=17
8=2y^2
y^2=4
Y= 2 x=7
y=-2 x=3

Answer 2

Y-x=-5
x^2-2xy-y^2=17
--------------
x=y+5
(y+5)^2-2y(y+5)-y^2=17
---------------------
x=y+5
y^2+10y+25-2y^2-10y-y^2=17
-------------------------
x=y+5
-2y^2=-8
---------
x=y+5
y^2=4
-----
x=y+5
y1=-2, y2=2
-----------
x1=3, x2=7
y1=-2, y2=2

ответ: (3; -2)v(7; 2)