AE = 41
ES = AE/2
ES = 41/2
ES = 20.5
ES = AS = FS = CS = 20.5
∆EFS = 50
∆EFS = ES + FS + EF
50 = 20.5 + 20.5 + EF
EF = 50 - 20.5 - 20.5
EF = 9
Chord EF = 9
CF = 50
CS = CF/2
CS = 50/2
CS = 25
CS = FS = ES = AS = 25
∆ACS = 60
∆ACS = CS + AS + AC
60 = 25 + 25 + AC
AC = 60 - 25 - 25
AC = 10
Chord AC = 10