Question

x^2-2x^2-9x+18=0
Решите уравнение

Answer 1

$x ^{2} - 2x ^{2} - 9x^{2} + 18 = 0$
$- {x}^{2} + 9x + 18 = 0 \ {x}^{2} + 9x - 18 = 0 \ D = 81 + 72 = 153 = 3 sqrt{17} \ x 1= frac{ - 9 + 3 sqrt{17} }{2} \ x2 = frac{ - 9 - 3 sqrt{17} }{2}$