Question

Найдите подбором корни уравнения
1. x²-8x-9=0
2. z²-3z-10=0
3.x²-17x+42=0
4. y²+11y-80=0

Answer 1

x² - 8x - 9 = 0
x₁ = 9    x₂ = - 1

z² - 3z - 10 = 0
z₁ = 5    z₂ = - 2

x² - 17x + 42 = 0
x₁ = 3     x₂ = 14

y² + 11y - 80 = 0
y₁ = 5      y₂ = - 16