Question

Resolva as equacoes de 2° gralX²+2x-8=0

Answer 1

Explicação passo-a-passo:

${x}^{2} + 2x - 8 = 0 \\ x = \frac{ - 2 + - \sqrt{ {2}^{2} - 4 \times 1 \times ( - 8)} }{2 \times 1} \\ \\ x = \frac{ - 2 + - \sqrt{4 + 32} }{2} \\ \\ x = \frac{ - 2 + - \sqrt{36} }{2} \\ \\ x1 = \frac{ - 2 + 6}{2} = \frac{4}{2} = 2 \\ \\ x2 = \frac{ - 2 - 6}{2} = \frac{ - 8}{2} = - 4$