Question

x ao quadrado -4x-12=0

Answer 1

x² - 4x - 12 = 0
a = 1
b = -4
c = -12

(delta) = b² - 4*a*c
(delta) = (-4)² - 4*1*(-12)
(delta) = 16 + 48
(delta) = 64

x = -b +ou- raiz de delta / 2*a
x = -(-4) +ou- raiz de 64 / 2*1
x = 4 +ou- 8 / 2
x1 = 4 + 8 / 2 --> 12 / 2 = 6
x1 = 4 - 8 / 2 ---> -4 / 2 = -2

Answer 2

x = - b +-√b²-4.a.c / 2.a

x = -(-4) +-√4²-4.1.12 / 2.a

x = +4 +-√16+48 / 2.a

x = 4+-√64 / 2.1

x = 4+-8 / 2.1

>> x' = 4+8 / 2.1   >> x' = 12/2 >> x'= 6
>> x'' = 4-8/ 2.1   >> x'' = -4/2 >>  x'' = -2

S = {-2 ; 6}