Question

Первая система под 4 номером

Answer 1

(√(x-1)+√(y+1))²=9
x-1+2√(xy+x-y-1)+y+1=9
2√(xy+x-y-1)=9-x-y
xy=5-x+y
2√(5-x+y+x-y-1)=9-x-y
2√4=9-x-y
2*2=9-x-y
x=9-4-y
x=5-y
y(5-y)=5-(5-y)+y
5y-y²=5-5+y+y
y²-3y=0
y(y-3)=0
y1=0⇒x1=5
y2=3⇒x2=2
Ответ (5;0);(2;3)