X2- 4x - 12=0 помогите прошу

Question

X2- 4x - 12=0 помогите прошу

Answer 1

х2 - 4х - 12 = 0

a b c

a = 1; b = -4; c = -12

D = b2 - 4ac

D = 16 - 4*1*(-12) = 16 + 48 = 64

√D = 8

x1,2 = (-b ± √D)/2a

х1 = (-(-4) - 8)/2*1 = -4/2 = -2;

х2 = (-(-4) + 8)/2*1 = 12/2 = 6.

Ответ: -2; 6.