∫BD = DC,ED=DH
A quadrilateral is a parallelogram.
∴BE∥CH,BE=CH
Point c is CF∨EH.
∫CH∨BE,CF∨EH
∴ quadrilateral EFCH is a parallelogram.
∴CH=EF,CF∥EH
∴BE=EF
∫CF∨EH
∴<; AFC =< doctorofaeronautics (abbreviation of doctor of aeronautics)
∵& lt; A =< doctorofaeronautics (abbreviation of Doctor of Aeronautics)
∴<; A =< automatic frequency control
△ AFC is an isosceles triangle.
Let cm?af be after point C.
∴FM=AM
Let BE=EF=a and AB=6.
∴AF=6-2a, then FM = af/2 = 3a.
Tan< AEC = cm/em = cm/(ef+FM) = cm/(a+3-a) = cm/3 = 4/3.
∴CM=4
∴s△abc= 1/2×ab×cm= 1/2×6×4= 12