Answer:
n₁ = 8
n₂ = - 3
Step-by-step explanation:
√(7n + 25) - n = 1
√(7n + 25) = n + 1
[√(7n + 25)]² = (n + 1)²
7n + 25 = n² + 2n + 1
n² + 2n + 1 - 7n - 25 = 0
n² - 5n - 24 = 0
n² + 3n - 8n - 24 = 0
n(n + 3) - 8(n + 3) = 0
(n - 8)(n + 3) = 0
n - 8 = 0 => n₁ = 8
n + 3 = 0 => n₂ = - 3
