-4x2 -10x +14 = 0
ax2 bx c = 0
a = -4
b = -10
c = 14
Δ = b2-4ac
Δ = -10² - (4 * -4 * 14)
Δ = 100 - (4*-56)
Δ = 100 - (-224)
Δ = 324 Δ > 0
-4x2-10x+14=0
x = -b ∓ √Δ 2a
x' = 10 - √324 2*-4 = 10 - 18.0 -8 = -8.0 -8 = 1.0
x" = 10 + √324 2*-4 = 10 + 18.0 -8 = 28.0 -8 = -3.5
x' = 16.0
x" = -56.0
S = {x ∈ R / x' = 16.0, x" = -56.0 }