Akar-akar persamaan kuadrat x² + x-90 = 0 adalah x₁ – x₂.​

-Persamaan Kuadrat-

x² + x – 90 = 0

x² + 10x – 9x – 90 = 0

x (x + 10) – 9 (x + 10) = 0

(x – 9)(x + 10) = 0

x₁ = 9 , x₂ = -10

x₁ – x₂

= 9 – (-10)

= 19