Question

Encontre as raízes da equação: x2 – 4x – 5 = 0
(Por favor incluir a conta)

:)

Answer 1

Explicação passo-a-passo:

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

$\Delta=(-4)^2-4\cdot1\cdot(-5)$

$\Delta=16+20$

$\Delta=36$

$x=\dfrac{-(-4)\pm\sqrt{36}}{2\cdot1}=\dfrac{4\pm6}{2}$

$x'=\dfrac{4+6}{2}~\longrightarrow~x'=\dfrac{10}{2}~\longrightarrow~x'=5$

$x"=\dfrac{4-6}{2}~\longrightarrow~x"=\dfrac{-2}{2}~\longrightarrow~x"=-1$