-4x2 -14x -6 = 0
ax2 bx c = 0
a = -4
b = -14
c = -6
Δ = b2-4ac
Δ = -14² - (4 * -4 * -6)
Δ = 196 - (4*24)
Δ = 196 - (96)
Δ = 100 Δ > 0
-4x2-14x-6=0
x = -b ∓ √Δ 2a
x' = 14 - √100 2*-4 = 14 - 10.0 -8 = 4.0 -8 = -0.5
x" = 14 + √100 2*-4 = 14 + 10.0 -8 = 24.0 -8 = -3.0
x' = -8.0
x" = -48.0
S = {x ∈ R / x' = -8.0, x" = -48.0 }