Question

5x2+12x-9=0
Пять икс в квадрате плюс двенадцать икс минус девять

Answer 1

$5x^2 + 12x - 9 = 0\\D = b^2 - 4ac = 12^2 - 4 * 5 * (-9) = 144 + 180 = 324\\\sqrt{D} = 18\\x = \frac{-b ± \sqrt{D} }{2a}\\x_1 = \frac{-12 + 18}{10} = \frac{6}{10} = 0,6\\\\x_2 = \frac{-12 - 18}{10} = -\frac{30}{10} = -3$

Answer 2

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