5x2 -16x +12 = 0
ax2 bx c = 0
a = 5
b = -16
c = 12
Δ = b2-4ac
Δ = -16² - (4 * 5 * 12)
Δ = 256 - (4*60)
Δ = 256 - (240)
Δ = 16 Δ > 0
5x2-16x+12=0
x = -b ∓ √Δ 2a
x' = 16 - √16 2*5 = 16 - 4.0 10 = 12.0 10 = 1.2
x" = 16 + √16 2*5 = 16 + 4.0 10 = 20.0 10 = 2.0
x' = 30.0
x" = 50.0
S = {x ∈ R / x' = 30.0, x" = 50.0 }