-12x2 +14x +6 = 0

ax2 bx c = 0

a = -12

b = 14

c = 6

Δ = b2-4ac

Δ = 14² - (4 * -12 * 6)

Δ = 196 - (4*-72)

Δ = 196 - (-288)

Δ = 484      Δ > 0

-12x2+14x+6=0

x = -b ∓ √Δ 2a

x' = -14 - √484 2*-12 = -14 - 22.0 -24 = -36.0 -24 = 1.5

x" = -14 + √484 2*-12 = -14 + 22.0 -24 = 8.0 -24 = -0.333333333333

x' = 216.0

x" = -48.0

S = {x ∈ R / x' = 216.0, x" = -48.0 }