-4x2 +17x -18 = 0

ax2 bx c = 0

a = -4

b = 17

c = -18

Δ = b2-4ac

Δ = 17² - (4 * -4 * -18)

Δ = 289 - (4*72)

Δ = 289 - (288)

Δ = 1      Δ > 0

-4x2+17x-18=0

x = -b ∓ √Δ 2a

x' = -17 - √1 2*-4 = -17 - 1.0 -8 = -18.0 -8 = 2.25

x" = -17 + √1 2*-4 = -17 + 1.0 -8 = -16.0 -8 = 2.0

x' = 36.0

x" = 32.0

S = {x ∈ R / x' = 36.0, x" = 32.0 }