X + Y = 10
X^2 + Y^2 = 58
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Y = 10 - X
Y^2 = 100 - 20X + X^2
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X^2 + 100 - 20X + X^2 = 58
2X^2 - 20X + 42 = 0
2 * ( X^2 - 10X + 21 ) = 0
D = 100 - 84 = 16
√ D = 4
X1 = ( 10 + 4 ) : 2 = 7
X2 = 6 : 2 = 3
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Y = 10 - X
Y1 = 10 - 7 = 3
Y2 = 10 - 3 = 7
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Ответ числа 7 и 3 ( или 3 и 7 )