Question

× la puterea 2 plus2×-8

Answer 1

${x}^{2} + 2x - 8 = 0$
∆ = 2²-4×1×(-8)=4+32=36
$x1 = \frac{ - 2 - \sqrt{36} }{2} = \frac{ - 2 - 6}{2} = \frac{ - 8}{2} = - 4$
$x2 = - \frac{ - 2 + \sqrt{36} }{2} = \frac{ - 2 + 6}{2} = \frac{4}{2} = 2$