Предмет: Алгебра, автор: GalaxyDeRay0

Зачем рассматривают x^2+4x+13 ? откуда это взялось? тупо откинули -y^2 чтоли?

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Автор ответа: winga123

не,из (2) ур-ия системы (2ху+4у=0 => у (х+2)=0) получили одно из решений, что у=0. Подставили в ур-ие (1), поэтому там "у" исчез. Потом рассмотрели второе решение, что х-2=0, знач., х=2 и снова подставили в (1)

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