15x2 +23x -14 = 0
ax2 bx c = 0
a = 15
b = 23
c = -14
Δ = b2-4ac
Δ = 23² - (4 * 15 * -14)
Δ = 529 - (4*-210)
Δ = 529 - (-840)
Δ = 1369 Δ > 0
15x2+23x-14=0
x = -b ∓ √Δ 2a
x' = -23 - √1369 2*15 = -23 - 37.0 30 = -60.0 30 = -2.0
x" = -23 + √1369 2*15 = -23 + 37.0 30 = 14.0 30 = 0.466666666667
x' = -450.0
x" = 105.0
S = {x ∈ R / x' = -450.0, x" = 105.0 }