X^2 - 3y = -5
x^2 - y = 1
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x^2 - 3(x^2 - 1) = -5
y = x^2 - 1
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x^2 - 3x^2 + 3 = -5
y = x^2 - 1
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-2x^2 = -5 - 3
y = x^2 - 1
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-2x^2 = -8
y = x^2 - 1
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x^2 = 4
y = x^2 - 1
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x_1 = 2
y_ 1= 2^2 - 1
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x_2 = -2
y_2 = (-2)^2 - 1
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x_1 = 2
y_1 = 3
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x_2 = -2
y_2 = 3
Ответ: (2;3) U (-2;3)