Question

Какое число является корнем уравнения 35:x=2+x ?

Answer 1

$35 \div x = 2 + x < = > \frac{35}{x} = 2 + x < = > 35 = (2 + x) \times x < = > 35 - (2 + x) \times x = 0 < = > 35 - (2x + x {}^{2} ) = 0 < = > 3x - 2x - x {}^{2} = 0 < = > - x {}^{2} - 2x + 35 = 0 < = > x {}^{2} + 2x - 35 = 0 < = > x = \frac{ - 2 \sqrt{2 {}^{2} - 4 \times 1 \times ( - 35) } }{2 \times 1} < = >$
$< = > x = \frac{ - 2 + - \sqrt{144} }{2}$
$< = > x = \frac{ - 2 + - 12}{2}$
$x = - 7$
или
$x = 5$