X2 - 2016x= y2 - 2016y
(x-y)(x+y -2016) =0 ⇔ [ y =x ; y = -x +2016 .
x²-2016*x=y²-2016*y
x²-y²-2016*x+2016*y=0
(x-y)*(x+y)-2016*(x-y)=0
(x-y)*(x+y-2016)=0
x=y
x+y-2016=0 x+y=2016 2x=2016 |÷2 x=1008 ⇒
Ответ: x=y=1008.