X - Y = - 9,7
XY = - 12.3
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X = Y - 9.7
Y * ( Y - 9.7) = - 12.3
Y^2 - 9.7Y + 12.3 = 0
D = 94.09 - 49.2 = 44.89
V D = 6.7
Y1 = ( 9.7 + 6.7) : 2 = 8.2
Y2 = 3 : 2 = 1.5
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X1 = 8.2 - 9.7 = ( - 1.5 )
X2 = 1.5 - 9.7 = ( - 8.2 )
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ответ числа ( - 1,5 ; 8.2 ) или ( - 8,2 ; 1,5 )