Solution: Make auxiliary lines GH = DF, He = AD, so that the triangle ADF is all equal to the triangle GHE, as shown in the figure:

Let df = x cm, then fc = 8-x cm.

The area of GFCH in trapezoid = the area of CEF in triangle-the area of ADF in triangle = 6.

The area of trapezoidal GFCH =[x+(8-x)]×ch \? 2=6

Solution: ch = 1.5

That is: CE = CH+He = 1.5+8 = 9.5 (cm).