-6x2 +19x -14 = 0

ax2 bx c = 0

a = -6

b = 19

c = -14

Δ = b2-4ac

Δ = 19² - (4 * -6 * -14)

Δ = 361 - (4*84)

Δ = 361 - (336)

Δ = 25      Δ > 0

-6x2+19x-14=0

x = -b ∓ √Δ 2a

x' = -19 - √25 2*-6 = -19 - 5.0 -12 = -24.0 -12 = 2.0

x" = -19 + √25 2*-6 = -19 + 5.0 -12 = -14.0 -12 = 1.16666666667

x' = 72.0

x" = 42.0

S = {x ∈ R / x' = 72.0, x" = 42.0 }