Question

x² - 3x - 4 = 0? pfv me ajudem ate hj gnt

Answer 1

a = 1, b = -3, c = -4
/\ = b² - 4ac
/\ = (-3)² - 4 . 1 . (-4)
/\ = 9 + 16
/\ = 25
x = [-(-3)+/- \/25]/2.1
x = [3+/-5]/2
x' = (3+5)/2 = 8/2 = 4
x" = (3-5)/2 = -2/2 = -1
S: {-1; 4}

Answer 2

Δ = b² - 4*a*c

Δ = (-3)² - 4*1*(-4)

Δ = 9 + 16

Δ = 25 

X = - b ± √Δ
      -----------
            2a

X = - (-3) ± √25
      ----------------
               2*1

X = 3 ± 5
      --------
          2


X1 = 8/2 = 4

X2 = -2/2 = -1

S: {4, -1}