By s (ABC) =18 =1/2ac * be =1/2 * AC * BC * sinc.
s(DEC)= 2 = 1/2 * EC * DF = 1/2 * EC * DC * sinC
Divide the two formulas to get: (AC/DC)*(BC/EC)=9.
Namely: (1/cosc) 2 = 9.
Germany: COSC = 1/3