As shown in the figure, it is known that in the quadrilateral ABCD, ad ‖ BC, ad > BC, ab = DC, EA = ed, EB and EC intersect ad at points F and g respectively to prove that the quadrilateral fbgc is isosceles trapezoid

As shown in the figure, it is known that in the quadrilateral ABCD, ad ‖ BC, ad > BC, ab = DC, EA = ed, EB and EC intersect ad at points F and g respectively to prove that the quadrilateral fbgc is isosceles trapezoid

∫ ad ∥ BC, be and CE intersect at e, that is, be and CE are not parallel, ∫ quadrilateral fbcg is trapezoid, ∫ ad ∥ BC, ad > BC, ∫ quadrilateral ABCD is trapezoid, ∫ AB = CD, ∫ trapezoid ABCD is isosceles trapezoid, ∫ bad = ∫ CDA, ∫ AE = De, ∫ ead = ∫ EDA, ∫ ead + ∫ bad = ∫ EDA + ∫ CDA, that is, ∫ EAB = ∫ EDC, ∫