Question

-x2 + 2x + 3 = 0
alguém???​

Answer 1

${ - x}^{2} + 2x + 3 = 0 \\ \alpha = {2}^{2} - 4 \times ( - 1) \times 3 \\ \alpha = 4 + 12 \\ \alpha = \sqrt{16} = 4 \\ x = \frac{ - 2 + - 4}{2} \\ x1 = \frac{2}{2} = 1 \\ x2 = \frac{ - 6}{2} = - 3$