Im linken dreieck:
sin(54,2°) = 6,1cm / EB
EB = 6,1 cm / sin(54,2°) = 7,52 cm
und winkel AEB = 35,8°
also winkel BEC = 62,5° - 35,8° = 26,7°
cos( 26,7°) = EB / EC = 7,52 cm / EC
EC = 7,52cm / cos( 26,7°) = 8,42 cm
ED^2 + CD^2 = EC^2
(4,9cm)^2 + CD^2 = ( 8,42 cm)^2
gibt CD^2 = 46,89cm^2
CD = 6,85cm
