Question

x+2×-3=0
$x {}^{2} + 2x - 3 = 0$

Answer 1

$x + 2x - 3 = 0 \\ 3x - 3 = 0 \\ 3x = 3 \\ x = 1$
${x}^{2} + 2x - 3 = 0 \\ delta = {b}^{2} - 4ac \\ delta = {2}^{2} - 4 \times 1 \times ( - 3) \\ delta \: = 4 + 12 \\ delta = 16 \\ \\ x = \frac{ - b + - \sqrt{delta} }{2a} \\ x = \frac{ - 2 + - \sqrt{16} }{2 \times 1} \\ x = \frac{- 2 + ou - 4}{2} \\ \: raiz \: 1 = \frac{ - 2 - 4}{2} = \frac{ - 6}{2} = - 3 \\ \\ raiz \: 2 = \frac{ - 2 + 4}{2} = \frac{2}{2} = 1$