5x2 -3x -2 = 0
ax2 bx c = 0
a = 5
b = -3
c = -2
Δ = b2-4ac
Δ = -3² - (4 * 5 * -2)
Δ = 9 - (4*-10)
Δ = 9 - (-40)
Δ = 49 Δ > 0
5x2-3x-2=0
x = -b ∓ √Δ 2a
x' = 3 - √49 2*5 = 3 - 7.0 10 = -4.0 10 = -0.4
x" = 3 + √49 2*5 = 3 + 7.0 10 = 10.0 10 = 1.0
x' = -10.0
x" = 25.0
S = {x ∈ R / x' = -10.0, x" = 25.0 }