5x2 -11x +2 = 0

ax2 bx c = 0

a = 5

b = -11

c = 2

Δ = b2-4ac

Δ = -11² - (4 * 5 * 2)

Δ = 121 - (4*10)

Δ = 121 - (40)

Δ = 81      Δ > 0

5x2-11x+2=0

x = -b ∓ √Δ 2a

x' = 11 - √81 2*5 = 11 - 9.0 10 = 2.0 10 = 0.2

x" = 11 + √81 2*5 = 11 + 9.0 10 = 20.0 10 = 2.0

x' = 5.0

x" = 50.0

S = {x ∈ R / x' = 5.0, x" = 50.0 }