2X^2 + 3 = 3 - 7X
2X^2 + 3 - 3 + 7X = 0
2X^2 + 7X = 0
2X * ( X + 3,5 ) = 0
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2X = 0
X = 0
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X + 3,5 = 0
X = - 3,5
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Ответ 0 ; - 3,5
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5X - 4Y = 12
X - 5Y = - 6
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X = 5Y - 6
5*( 5Y - 6) - 4Y = 12
25Y - 30 - 4Y =12
21Y = 42
Y = 2
X = 10 - 6 = 4
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Ответ X = 4 ; Y = 2
( 5x - 15 )( 5x + 15 ) - 25x^2 + 10x - 10 = 25x^2 - 225 - 25x^2 + 10x - 10 = - 225 + 10x - 10 = - 235 + 10x
X = 130
- 235 + 10•130 = - 235 + 1300 = 1065
250, 520, 502
250, 520, 205,
520, 250
нету
502
205