A(0, 0), B(52.6, 0), C(26.3, 1.9)
AB的中点C'(26.3, 0), 中垂线p方程: x = 26.3
AC的中点B'(13.15, 0.95), 斜率k = 1.9/26.3, 中垂线斜率k' = -1/k = -26.3/1.9,
中垂线方程q: y - 0.95 = (-26.3/1.9)(x - 13.15)
联立得圆心D(26.3, -181.07)
半径r = √[26.3² + (-181.07)²] = 182.97
直径d = 2r = 365.94