-73/5 * (-73/5 + 10) - (-73/5 + 5) * (-73/5 - 5)

Let x = -73/5. The expression becomes x * (x + 10) - (x + 5) * (x - 5). This simplifies to x^2 + 10x - (x^2 - 25). Further simplification yields x^2 + 10x - x^2 + 25 = 10x + 25. Substituting x = -73/5, we get 10 * (-73/5) + 25 = 2 * (-73) + 25 = -146 + 25 = -121.