Ответ:

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2x² - 7x - 30 = 0

D = b² - 4ac

a = 2

b = -7

c = -30

D = (-7)² - 4 * 2 * (-30) = 49 + 240 = 289 (√289 = 17)

x1 = (7 + 17)/2 = 24/2 = 12

x2 = (7 - 17)/2 = -10/2 = -5

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Ответ:

D = 289 it is determinant

x1 = 6

x2 = -2.5