-6x2 +15x -9 = 0
ax2 bx c = 0
a = -6
b = 15
c = -9
Δ = b2-4ac
Δ = 15² - (4 * -6 * -9)
Δ = 225 - (4*54)
Δ = 225 - (216)
Δ = 9 Δ > 0
-6x2+15x-9=0
x = -b ∓ √Δ 2a
x' = -15 - √9 2*-6 = -15 - 3.0 -12 = -18.0 -12 = 1.5
x" = -15 + √9 2*-6 = -15 + 3.0 -12 = -12.0 -12 = 1.0
x' = 54.0
x" = 36.0
S = {x ∈ R / x' = 54.0, x" = 36.0 }