x² - 2x - 7 = 0
x₁ + x₂ = 2
x₁ * x₂ = - 7
5x₁x₂ - x₁ - x₂ = 5x₁x₂ - 5(x₁ + x₂) = 5 * (- 7) - 5 * 2 = - 35 - 10 = - 45
x² - 2x - 7 = 0
x₁ + x₂ = 2
x₁ * x₂ = - 7
5x₁x₂ - x₁ - x₂ = 5x₁x₂ - 5(x₁ + x₂) = 5 * (- 7) - 5 * 2 = - 35 - 10 = - 45