5x2 +17x +6 = 0

ax2 bx c = 0

a = 5

b = 17

c = 6

Δ = b2-4ac

Δ = 17² - (4 * 5 * 6)

Δ = 289 - (4*30)

Δ = 289 - (120)

Δ = 169      Δ > 0

5x2+17x+6=0

x = -b ∓ √Δ 2a

x' = -17 - √169 2*5 = -17 - 13.0 10 = -30.0 10 = -3.0

x" = -17 + √169 2*5 = -17 + 13.0 10 = -4.0 10 = -0.4

x' = -75.0

x" = -10.0

S = {x ∈ R / x' = -75.0, x" = -10.0 }