(2 * (5 * 3 + 3.5 * 2.5) - (5 + 3.5) * (3 + 2.5)) / (sqrt(2 * (5^2 + 3.5^2) - (5 + 3.5)^2) * sqrt(2 * (3^2 + 2.5^2) - (3 + 2.5)^2))