Корень из (2X^2-7X-9) минус X=1

√ (2x² - 7x - 9) - x = 1

√ (2x² - x - 9) = x + 1

2x² - x - 9 = (x + 1) ²

2x² - x - 9 = (x + 1) (x + 1)

2x² - x - 9 = x² + x + x + 1

2x² - x - 9 = x² + 2x + 1

2x² - x - 9 - x² - 2x - 1 = 0

x² - 3x - 10 = 0

D = b² - 4ac = 9 - 4 * 1 * (- 10) = 9 + 40 = 49 = 7²

x₁ = 3 + 7 / 2 = 5

x₂ = 3 - 7 / 2 = - 4 / 2 = - 2

Ответ: x₁ = 5, x₂ = - 2