-4x2 +2x +6 = 0

ax2 bx c = 0

a = -4

b = 2

c = 6

Δ = b2-4ac

Δ = 2² - (4 * -4 * 6)

Δ = 4 - (4*-24)

Δ = 4 - (-96)

Δ = 100      Δ > 0

-4x2+2x+6=0

x = -b ∓ √Δ 2a

x' = -2 - √100 2*-4 = -2 - 10.0 -8 = -12.0 -8 = 1.5

x" = -2 + √100 2*-4 = -2 + 10.0 -8 = 8.0 -8 = -1.0

x' = 24.0

x" = -16.0

S = {x ∈ R / x' = 24.0, x" = -16.0 }