-9x2 -17x +2 = 0

ax2 bx c = 0

a = -9

b = -17

c = 2

Δ = b2-4ac

Δ = -17² - (4 * -9 * 2)

Δ = 289 - (4*-18)

Δ = 289 - (-72)

Δ = 361      Δ > 0

-9x2-17x+2=0

x = -b ∓ √Δ 2a

x' = 17 - √361 2*-9 = 17 - 19.0 -18 = -2.0 -18 = 0.111111111111

x" = 17 + √361 2*-9 = 17 + 19.0 -18 = 36.0 -18 = -2.0

x' = 9.0

x" = -162.0

S = {x ∈ R / x' = 9.0, x" = -162.0 }