Question

RESOLVA A EQUAÇAO DE SEGUNDO GRAU:



X AO QUADRADO -3X+2=42

Answer 1

Olá.

$\cdot \: x^{2} - 3x + 2 = 42 \\ \\ x^{2} - 3x + 2 = 42 \\ x^{2} -3x - 40 = 0$

$a = 1 \\ b = -3 \\ c = -40$

$x = \frac{-b \pm \sqrt{\triangle}}{2a} \\ \\ x = \frac{3 \pm \sqrt{(-3)^{2} - 4(1)(-40)}}{2} \\ \\ x= \frac{3 \pm \sqrt{169}}{2} \\ \\ x = \frac{3 \pm 13}{2}$


$x_{1} = \frac{3 + 13}{2} = 8 \\ \\ x_{2} = \frac{3 - 13}{2} = -5$

$\framebox{S = {-5, \: 8}}$

Bons estudos.