5x2 +22x +17 = 0
ax2 bx c = 0
a = 5
b = 22
c = 17
Δ = b2-4ac
Δ = 22² - (4 * 5 * 17)
Δ = 484 - (4*85)
Δ = 484 - (340)
Δ = 144 Δ > 0
5x2+22x+17=0
x = -b ∓ √Δ 2a
x' = -22 - √144 2*5 = -22 - 12.0 10 = -34.0 10 = -3.4
x" = -22 + √144 2*5 = -22 + 12.0 10 = -10.0 10 = -1.0
x' = -85.0
x" = -25.0
S = {x ∈ R / x' = -85.0, x" = -25.0 }