-12x2 -19x +18 = 0
ax2 bx c = 0
a = -12
b = -19
c = 18
Δ = b2-4ac
Δ = -19² - (4 * -12 * 18)
Δ = 361 - (4*-216)
Δ = 361 - (-864)
Δ = 1225 Δ > 0
-12x2-19x+18=0
x = -b ∓ √Δ 2a
x' = 19 - √1225 2*-12 = 19 - 35.0 -24 = -16.0 -24 = 0.666666666667
x" = 19 + √1225 2*-12 = 19 + 35.0 -24 = 54.0 -24 = -2.25
x' = 96.0
x" = -324.0
S = {x ∈ R / x' = 96.0, x" = -324.0 }