Question

x2 - x - 12 = 0

a) -4, 3
b) -4, -3
c) 4, -3
d) 4,3
e) N.D.A​

Answer 1

Resposta:

c) 4, -3

Explicação passo-a-passo:

x2 - x - 12 = 0

a=1

b=-1

c=-12

∆=b²-4ac

∆=(-1)²-4×1×-12

∆=1+48

∆=49

-b±√∆/2a

1±√49/2×1

1±7/2

x¹=1+7/2=8/2=4

x²=1-7/2=-6/2=-3