22x2 +11x -11 = 0

ax2 bx c = 0

a = 22

b = 11

c = -11

Δ = b2-4ac

Δ = 11² - (4 * 22 * -11)

Δ = 121 - (4*-242)

Δ = 121 - (-968)

Δ = 1089      Δ > 0

22x2+11x-11=0

x = -b ∓ √Δ 2a

x' = -11 - √1089 2*22 = -11 - 33.0 44 = -44.0 44 = -1.0

x" = -11 + √1089 2*22 = -11 + 33.0 44 = 22.0 44 = 0.5

x' = -484.0

x" = 242.0

S = {x ∈ R / x' = -484.0, x" = 242.0 }