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( - 0,2p - 10q)^2 =
= ( - 0,2p)^2 - 2( - 0.2p)*10q + 100q^2 =
= 0,04p^2 + 4pq + 100q^2
X^2 + 2Y^2 = 36
3X^2 - 2Y^2 = - 20
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X^2 + 3X^2 + 2Y^2 - 2Y^2 = 36 - 20
4X^2 = 16
X^2 = 4
X1 = 2
X2 = - 2
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X^2 + 2Y^2 = 36
4 + 2Y^2 = 36
2Y^2 = 32
Y^2 = 16
Y1 = 4
Y2 = - 4
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Ответ ( 2 ; 4 ) ; ( - 2 ; - 4 )