-6x2 -7x +13 = 0
ax2 bx c = 0
a = -6
b = -7
c = 13
Δ = b2-4ac
Δ = -7² - (4 * -6 * 13)
Δ = 49 - (4*-78)
Δ = 49 - (-312)
Δ = 361 Δ > 0
-6x2-7x+13=0
x = -b ∓ √Δ 2a
x' = 7 - √361 2*-6 = 7 - 19.0 -12 = -12.0 -12 = 1.0
x" = 7 + √361 2*-6 = 7 + 19.0 -12 = 26.0 -12 = -2.16666666667
x' = 36.0
x" = -78.0
S = {x ∈ R / x' = 36.0, x" = -78.0 }