Maths problem: how to do, thanks?

△ABC ～ △ADE
AC/AB = AE/AD
1o/8 = (8+14)/(1o+CD)
∴ CD = 22/(1o/8) - 1o = 7.6 (cm)

DE = √(AE^2-AD^2) = √(22^2-17.6^2) = 13.2
EC = √(13.2^2+7.6^2) = √232
圓BCDE半徑 = √232/2 = √58(cm)