-6x2 -11x -4 = 0
ax2 bx c = 0
a = -6
b = -11
c = -4
Δ = b2-4ac
Δ = -11² - (4 * -6 * -4)
Δ = 121 - (4*24)
Δ = 121 - (96)
Δ = 25 Δ > 0
-6x2-11x-4=0
x = -b ∓ √Δ 2a
x' = 11 - √25 2*-6 = 11 - 5.0 -12 = 6.0 -12 = -0.5
x" = 11 + √25 2*-6 = 11 + 5.0 -12 = 16.0 -12 = -1.33333333333
x' = -18.0
x" = -48.0
S = {x ∈ R / x' = -18.0, x" = -48.0 }