18x2 -12x -6 = 0
ax2 bx c = 0
a = 18
b = -12
c = -6
Δ = b2-4ac
Δ = -12² - (4 * 18 * -6)
Δ = 144 - (4*-108)
Δ = 144 - (-432)
Δ = 576 Δ > 0
18x2-12x-6=0
x = -b ∓ √Δ 2a
x' = 12 - √576 2*18 = 12 - 24.0 36 = -12.0 36 = -0.333333333333
x" = 12 + √576 2*18 = 12 + 24.0 36 = 36.0 36 = 1.0
x' = -108.0
x" = 324.0
S = {x ∈ R / x' = -108.0, x" = 324.0 }