-4x2 -11x -6 = 0
ax2 bx c = 0
a = -4
b = -11
c = -6
Δ = b2-4ac
Δ = -11² - (4 * -4 * -6)
Δ = 121 - (4*24)
Δ = 121 - (96)
Δ = 25 Δ > 0
-4x2-11x-6=0
x = -b ∓ √Δ 2a
x' = 11 - √25 2*-4 = 11 - 5.0 -8 = 6.0 -8 = -0.75
x" = 11 + √25 2*-4 = 11 + 5.0 -8 = 16.0 -8 = -2.0
x' = -12.0
x" = -32.0
S = {x ∈ R / x' = -12.0, x" = -32.0 }