Question 85
Let $p$ be a prime number. Find all positive integers $x, y \gt 1$ such that
$$
\frac{x^2 - 1}{y^2 - 1} = (p + 1)^2.
$$
$$
\frac{x^2 - 1}{y^2 - 1} = (p + 1)^2.
$$
Math Olympiad Vault · MathNet 2025 — Part 02 (100 complete bilingual questions)