5x2 +14x -19 = 0
ax2 bx c = 0
a = 5
b = 14
c = -19
Δ = b2-4ac
Δ = 14² - (4 * 5 * -19)
Δ = 196 - (4*-95)
Δ = 196 - (-380)
Δ = 576 Δ > 0
5x2+14x-19=0
x = -b ∓ √Δ 2a
x' = -14 - √576 2*5 = -14 - 24.0 10 = -38.0 10 = -3.8
x" = -14 + √576 2*5 = -14 + 24.0 10 = 10.0 10 = 1.0
x' = -95.0
x" = 25.0
S = {x ∈ R / x' = -95.0, x" = 25.0 }