-4x2 +18x -8 = 0

ax2 bx c = 0

a = -4

b = 18

c = -8

Δ = b2-4ac

Δ = 18² - (4 * -4 * -8)

Δ = 324 - (4*32)

Δ = 324 - (128)

Δ = 196      Δ > 0

-4x2+18x-8=0

x = -b ∓ √Δ 2a

x' = -18 - √196 2*-4 = -18 - 14.0 -8 = -32.0 -8 = 4.0

x" = -18 + √196 2*-4 = -18 + 14.0 -8 = -4.0 -8 = 0.5

x' = 64.0

x" = 8.0

S = {x ∈ R / x' = 64.0, x" = 8.0 }