Question

x²- 6x - 7 = 0 Дискриминат​

Answer 1

$x^{2} - 6x - 7 = 0$

$a = 1; b = -6; c = -7$

$D = b^{2} - 4ac = (-6)^{2} - 4 * 1 * (-7) = 36 + 28 = 64 = 8^{2}$

x₁₂ = -b ± $\sqrt{D}$ / 2a = -(-6) ± $\sqrt{64}$ / 2 * 1

x₁ = $\frac{6+8}{2} = \frac{14}{2} = 7$

x₂ = $\frac{6-8}{2} = -\frac{2}{2} = -1$

Ответ: -1, 7