Y = X - 1
...............................
X^2 + Y^2 = 25
X^2 + X^2 - 2X + 1 - 25 = 0
2X^2 - 2X - 24 = 0 ( : 2 )
X^2 - X - 12 = 0
D = 1 - 4*1*(-12) = 1 + 48 = 49 ; V D = 7
X1 = ( 1 + 7) : 2 = 4
X2 = ( - 6) : 2 = ( - 3 )
..............................
Y = X - 1
Y1 = 4 - 1 = 3
Y2 = - 3 - 1 = - 4
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ОТВЕТ: ( 4 ; 3 ) U ( - 3 ; - 4 )