Question

Encontre a raiz da equação: x²- 4x-5=0

Answer 1

$x^{2} - 4x - 5 = 0$

Δ = b²−4ac
Δ = (−4)²−4⋅1⋅−5
Δ = 16 + 20
Δ = 36

$x = \dfrac{-b \pm \sqrt{\Delta}}{2*a}\\ \\ \\x = \dfrac{-(-4) \pm \sqrt{36}}{2*1}\\ \\ \\x = \dfrac{4 \pm 6}{2}\\ \\ \\x' = \dfrac{4 + 6}{2}\\ \\ \\x' = \dfrac{10}{2}\\ \\ \\x' = 5\\ \\ \\x'' = \dfrac{4 - 6}{2}\\ \\ \\x'' = \dfrac{-2}{2}\\ \\ \\x'' = -1$

S = (5, -1)