Question

помогите решить
$\frac{4}{7} + \times (x - 1) = \frac{2}{7} + x$
​

Answer 1

Ответ:

$x_{1} = \frac{7-\sqrt{35} }{7} , x_{2} = \frac{7+\sqrt{35} }{7}$

Пошаговое объяснение:

$\frac{4}{7} + x *(x - 1) = \frac{2}{7} + x\\\\\frac{4}{7} + x^{2} - x = \frac{2}{7} + x\\\\4 + 7x^{2} - 7x = 2 + 7x\\\\4 + 7x^{2} - 7x - 2 - 7x = 0\\\\2 + 7x^{2} - 14x = 0\\\\7x^{2} - 14x + 2 = 0\\\\x = \frac{-(-14) + \sqrt{(-14)^{2}- 4 * 7 * 2 } }{2 * 7} \\\\x = \frac{14 + \sqrt{196 - 56} }{14} \\\\x = \frac{14 + \sqrt{140} }{14} \\\\x = \frac{14 + 2 \sqrt{35} }{14} \\\\x = \frac{14 + 2\sqrt{35} }{14} \\x = \frac{14 - 2\sqrt{35} }{14} \\\\x = \frac{7 +\sqrt{35} }{7}$ \\$x = \frac{7 - \sqrt{35} }{7} \\\\OTBET: x_{1} = \frac{7 -\sqrt{35} }{7} , x_{2} = \frac{7 + \sqrt{35} }{7}$