Question

(x-9)^2=(x+4) найдите корень уравнения

Answer 1

x² - 18x + 81 = x+4,
x² - 19x + 77 = 0,
D = 19² - 4*77 = 361 - 308 = 53,
$x = \frac{19\pm \sqrt{53}}{2}$
$x_1 = \frac{19 - \sqrt{53}}{2}$
$x_2 = \frac{19+\sqrt{53}}{2}$