5x2 +23x -10 = 0
ax2 bx c = 0
a = 5
b = 23
c = -10
Δ = b2-4ac
Δ = 23² - (4 * 5 * -10)
Δ = 529 - (4*-50)
Δ = 529 - (-200)
Δ = 729 Δ > 0
5x2+23x-10=0
x = -b ∓ √Δ 2a
x' = -23 - √729 2*5 = -23 - 27.0 10 = -50.0 10 = -5.0
x" = -23 + √729 2*5 = -23 + 27.0 10 = 4.0 10 = 0.4
x' = -125.0
x" = 10.0
S = {x ∈ R / x' = -125.0, x" = 10.0 }