-3x2 +19x +14 = 0

ax2 bx c = 0

a = -3

b = 19

c = 14

Δ = b2-4ac

Δ = 19² - (4 * -3 * 14)

Δ = 361 - (4*-42)

Δ = 361 - (-168)

Δ = 529      Δ > 0

-3x2+19x+14=0

x = -b ∓ √Δ 2a

x' = -19 - √529 2*-3 = -19 - 23.0 -6 = -42.0 -6 = 7.0

x" = -19 + √529 2*-3 = -19 + 23.0 -6 = 4.0 -6 = -0.666666666667

x' = 63.0

x" = -6.0

S = {x ∈ R / x' = 63.0, x" = -6.0 }