Question

x² +2x-8=0 preciso das operaçao

Answer 1

$x = \frac{- b +- \sqrt{b^{2} - 4*a*c} }{2 *a}$
a = 1
b = 2
c = - 8

$x = \frac{- 2 +- \sqrt{2^{2} - 4*1*(-8)} }{2 *1}$
$x = \frac{- 2 +- \sqrt{4 + 32} }{2}$
$x = \frac{- 2 +- \sqrt{36} }{2}$
$x = \frac{- 2 +- 6 }{2}$

$x^{1} = \frac{- 2 + 6 }{2}$
$x^{1} = \frac{4 }{2}$
$x^{1} = 2$

$x^{2} = \frac{- 2 - 6 }{2}$
$x^{2} = \frac{- 8 }{2}$
$x^{2} = -4$

Answer 2

X² +2x-8=0
a = 1; b = +2; c = -8

Δ=b² - 4.a.c
=2²-4.1.(-8)
=4+32
=36

x = -b ± √ Δ/ 2.a
x = -2± √36/2.1
x' = -2+6/2
= 4/2
= 2
x" = -2-6/2
= -8/2
= -4
S = {-4, 2}