-6x2 +22x -20 = 0
ax2 bx c = 0
a = -6
b = 22
c = -20
Δ = b2-4ac
Δ = 22² - (4 * -6 * -20)
Δ = 484 - (4*120)
Δ = 484 - (480)
Δ = 4 Δ > 0
-6x2+22x-20=0
x = -b ∓ √Δ 2a
x' = -22 - √4 2*-6 = -22 - 2.0 -12 = -24.0 -12 = 2.0
x" = -22 + √4 2*-6 = -22 + 2.0 -12 = -20.0 -12 = 1.66666666667
x' = 72.0
x" = 60.0
S = {x ∈ R / x' = 72.0, x" = 60.0 }