Verified answer

Resposta:

[tex]\textsf{Leia abaixo}[/tex]

Explicação passo a passo:

[tex]\mathsf{-x^2 - 4x + 5 = 0}[/tex]

[tex]\mathsf{x^2 + 4x - 5 = 0}[/tex]

[tex]\mathsf{\Delta = b^2 - 4.a.c}[/tex]

[tex]\mathsf{\Delta = 4^2 - 4.1.(-5)}[/tex]

[tex]\mathsf{\Delta = 16 + 20}[/tex]

[tex]\mathsf{\Delta = 36}[/tex]

[tex]\mathsf{x = \dfrac{-b \pm \sqrt{\Delta}}{2a} = \dfrac{-4 \pm \sqrt{36}}{2} \rightarrow \begin{cases}\mathsf{x' = \dfrac{-4 + 6}{2} = \dfrac{2}{2} = 1}\\\\\mathsf{x'' = \dfrac{-4 - 6}{2} = -\dfrac{10}{2} = -5}\end{cases}}[/tex]

[tex]\boxed{\boxed{\mathsf{S = \{1;-5\}}}}[/tex]