Question

3) y2 - 10y -25 = 0.
Решить

Answer 1

Ответ:

$x_{1/2} = 5б5\sqrt{2}.$

Пошаговое объяснение:

$y^{2} - 10y - 25 = 0\\D = b^2 - 4ac\\D = (-10)^2 - 4 * 1 * (-25) = 100 + 100 = 200\\x_{1/2} = \dfrac{-b б \sqrt{D} }{2a} \\\\x_{1/2}= \dfrac{10б\sqrt{200} }{2} = \dfrac{10б\sqrt{100*2} }{2} = \dfrac{10б10\sqrt{2} }{2} = 5 б 5\sqrt{2}.$