-4x2 +18x +22 = 0
ax2 bx c = 0
a = -4
b = 18
c = 22
Δ = b2-4ac
Δ = 18² - (4 * -4 * 22)
Δ = 324 - (4*-88)
Δ = 324 - (-352)
Δ = 676 Δ > 0
-4x2+18x+22=0
x = -b ∓ √Δ 2a
x' = -18 - √676 2*-4 = -18 - 26.0 -8 = -44.0 -8 = 5.5
x" = -18 + √676 2*-4 = -18 + 26.0 -8 = 8.0 -8 = -1.0
x' = 88.0
x" = -16.0
S = {x ∈ R / x' = 88.0, x" = -16.0 }