Question

решите плиз у меня экзамен

Answer 1

$frac{ x^{2} -7x}{x-4}- frac{12}{4-x} =0$
$frac{ x^{2} -7x}{x-4} + frac{12}{x-4}=0$
$frac{ x^{2} -7x+12}{x-4} =0$
x² - 7x + 12 = 0                                                  x - 4 ≠ 0
D = 49 - 4 * 12 = 49 - 48 = 1                              x ≠ 4
$X _{1} = frac{7- sqrt{1} }{2} = frac{7-1}{2} =3$
$X _{2}= frac{7+ sqrt{1} }{2} = frac{7+1}{2} =4$ - не уд
Ответ: 3