-9x2 -18x -9 = 0
ax2 bx c = 0
a = -9
b = -18
c = -9
Δ = b2-4ac
Δ = -18² - (4 * -9 * -9)
Δ = 324 - (4*81)
Δ = 324 - (324)
Δ = 0 Δ = 0
x = -b 2*a
x = 18 2*-9
x = -1.0
S = {x ∈ R / x = -1.0}
-9x2 -18x -9 = 0
ax2 bx c = 0
a = -9
b = -18
c = -9
Δ = b2-4ac
Δ = -18² - (4 * -9 * -9)
Δ = 324 - (4*81)
Δ = 324 - (324)
Δ = 0 Δ = 0
x = -b 2*a
x = 18 2*-9
x = -1.0
S = {x ∈ R / x = -1.0}