Question

Решите ур-ние: x²+18=10-6x

Answer 1

x² + 18 = 10 - 6x
x² + 6x + 18 - 10 = 0
x² + 6x + 8 = 0
D = b² - 4ac = 6² - 4*1*8 = 36 - 32 = 4
√D = √4 = 2

$x_1= frac{-b+ sqrt{D} }{2a} = frac{-6+2}{2} = frac{-4}{2} = -2$
$x_2 = frac{-b-sqrt{D} }{2a}= frac{-6-2}{2} = frac{-8}{2} = -4$

Ответ: -4; -2