5x2 -2x -16 = 0
ax2 bx c = 0
a = 5
b = -2
c = -16
Δ = b2-4ac
Δ = -2² - (4 * 5 * -16)
Δ = 4 - (4*-80)
Δ = 4 - (-320)
Δ = 324 Δ > 0
5x2-2x-16=0
x = -b ∓ √Δ 2a
x' = 2 - √324 2*5 = 2 - 18.0 10 = -16.0 10 = -1.6
x" = 2 + √324 2*5 = 2 + 18.0 10 = 20.0 10 = 2.0
x' = -40.0
x" = 50.0
S = {x ∈ R / x' = -40.0, x" = 50.0 }