22x2 +13x -9 = 0
ax2 bx c = 0
a = 22
b = 13
c = -9
Δ = b2-4ac
Δ = 13² - (4 * 22 * -9)
Δ = 169 - (4*-198)
Δ = 169 - (-792)
Δ = 961 Δ > 0
22x2+13x-9=0
x = -b ∓ √Δ 2a
x' = -13 - √961 2*22 = -13 - 31.0 44 = -44.0 44 = -1.0
x" = -13 + √961 2*22 = -13 + 31.0 44 = 18.0 44 = 0.409090909091
x' = -484.0
x" = 198.0
S = {x ∈ R / x' = -484.0, x" = 198.0 }