-1x2 -10x -16 = 0

ax2 bx c = 0

a = -1

b = -10

c = -16

Δ = b2-4ac

Δ = -10² - (4 * -1 * -16)

Δ = 100 - (4*16)

Δ = 100 - (64)

Δ = 36      Δ > 0

-x2-10x-16=0

x = -b ∓ √Δ 2a

x' = 10 - √36 2*-1 = 10 - 6.0 -2 = 4.0 -2 = -2.0

x" = 10 + √36 2*-1 = 10 + 6.0 -2 = 16.0 -2 = -8.0

x' = -2.0

x" = -8.0

S = {x ∈ R / x' = -2.0, x" = -8.0 }