-4x2 +14x -10 = 0
ax2 bx c = 0
a = -4
b = 14
c = -10
Δ = b2-4ac
Δ = 14² - (4 * -4 * -10)
Δ = 196 - (4*40)
Δ = 196 - (160)
Δ = 36 Δ > 0
-4x2+14x-10=0
x = -b ∓ √Δ 2a
x' = -14 - √36 2*-4 = -14 - 6.0 -8 = -20.0 -8 = 2.5
x" = -14 + √36 2*-4 = -14 + 6.0 -8 = -8.0 -8 = 1.0
x' = 40.0
x" = 16.0
S = {x ∈ R / x' = 40.0, x" = 16.0 }