Question

Пожалуйста помогите с алгеброй!!!!​

Answer 1

Ответ:

${x}^{2} - 9x - 10 = {x}^{2} - 2 \times x \times 4.5 + 20.25 - 30.25 = {x - 4.5}^{2} - {5.5}^{2}$

$x1 + x2 = - 9 \\ x1 \times x2 = - 10 \\ x1 = 10 \\ x2 = - 1 \\ (x - 1)(x + 10)$

${x}^{2} - 6 |x| + 8 = 0 \\ {x}^{2} = { |x| }^{2} \\ {x}^{2} - 6x + 8 = 0 \\ {x}^{2} - 6x - 8 = 0 \\ d1 = 36 - 4 \times 8 = 4 > 0 \\ x 1 = \frac{6 + 2}{2} = 4 \\ x2 = \frac{6 - 2}{2} = 2 \\ d2 = 36 - 4 \times ( - 8) = 68 > 0 \\ x3 = \frac{ 6 - \sqrt{68} }{2} = \frac{2(3 - \sqrt{17}) }{2} = 3 - \sqrt{17} \\ x4 = \frac{6 + \sqrt{68} }{2} = \frac{2(3 + \sqrt{17)} }{2} = 3 + \sqrt{17}$