Question

Determinar as raízes do polinomio;
A (x) = x2 - 4x - 5

Answer 1

${x}^{2} - 4x - 5 = 0 \\ \\ delta = 16 + 20 = 36 \\ \\ x = \frac{ 4 + \sqrt{36} }{2} = \frac{4 + 6}{2} = \frac{10}{2} = 5 \\ \\ x = \frac{4 - \sqrt{36} }{2} = \frac{4 - 6}{2} = \frac{ - 2}{2} = - 1$
Logo, as raízes são -2 e 5.