-4x2 +6x +4 = 0

ax2 bx c = 0

a = -4

b = 6

c = 4

Δ = b2-4ac

Δ = 6² - (4 * -4 * 4)

Δ = 36 - (4*-16)

Δ = 36 - (-64)

Δ = 100      Δ > 0

-4x2+6x+4=0

x = -b ∓ √Δ 2a

x' = -6 - √100 2*-4 = -6 - 10.0 -8 = -16.0 -8 = 2.0

x" = -6 + √100 2*-4 = -6 + 10.0 -8 = 4.0 -8 = -0.5

x' = 32.0

x" = -8.0

S = {x ∈ R / x' = 32.0, x" = -8.0 }