-12x2 +23x -11 = 0

ax2 bx c = 0

a = -12

b = 23

c = -11

Δ = b2-4ac

Δ = 23² - (4 * -12 * -11)

Δ = 529 - (4*132)

Δ = 529 - (528)

Δ = 1      Δ > 0

-12x2+23x-11=0

x = -b ∓ √Δ 2a

x' = -23 - √1 2*-12 = -23 - 1.0 -24 = -24.0 -24 = 1.0

x" = -23 + √1 2*-12 = -23 + 1.0 -24 = -22.0 -24 = 0.916666666667

x' = 144.0

x" = 132.0

S = {x ∈ R / x' = 144.0, x" = 132.0 }