5x2 +16x +3 = 0
ax2 bx c = 0
a = 5
b = 16
c = 3
Δ = b2-4ac
Δ = 16² - (4 * 5 * 3)
Δ = 256 - (4*15)
Δ = 256 - (60)
Δ = 196 Δ > 0
5x2+16x+3=0
x = -b ∓ √Δ 2a
x' = -16 - √196 2*5 = -16 - 14.0 10 = -30.0 10 = -3.0
x" = -16 + √196 2*5 = -16 + 14.0 10 = -2.0 10 = -0.2
x' = -75.0
x" = -5.0
S = {x ∈ R / x' = -75.0, x" = -5.0 }