-12x2 -10x -2 = 0

ax2 bx c = 0

a = -12

b = -10

c = -2

Δ = b2-4ac

Δ = -10² - (4 * -12 * -2)

Δ = 100 - (4*24)

Δ = 100 - (96)

Δ = 4      Δ > 0

-12x2-10x-2=0

x = -b ∓ √Δ 2a

x' = 10 - √4 2*-12 = 10 - 2.0 -24 = 8.0 -24 = -0.333333333333

x" = 10 + √4 2*-12 = 10 + 2.0 -24 = 12.0 -24 = -0.5

x' = -48.0

x" = -72.0

S = {x ∈ R / x' = -48.0, x" = -72.0 }