-6x2 -17x -5 = 0
ax2 bx c = 0
a = -6
b = -17
c = -5
Δ = b2-4ac
Δ = -17² - (4 * -6 * -5)
Δ = 289 - (4*30)
Δ = 289 - (120)
Δ = 169 Δ > 0
-6x2-17x-5=0
x = -b ∓ √Δ 2a
x' = 17 - √169 2*-6 = 17 - 13.0 -12 = 4.0 -12 = -0.333333333333
x" = 17 + √169 2*-6 = 17 + 13.0 -12 = 30.0 -12 = -2.5
x' = -12.0
x" = -90.0
S = {x ∈ R / x' = -12.0, x" = -90.0 }