Author:Zlatan Magajna (Tue Jul 12 04:00:22 2016)
Source: C:\ Users\ Zlatan\ zm\ Proj\ GeoOkApp\ OkExamples\ Trapezium2.pro

# TaskC

| ### 1 Task HereC is a trapezium ABCD. The point E is the intersection of the diagonals. Prove that the areas of triangles AED and BEC are equal. Comment: xxx

| ### 2 parallel lines Claim 1 AB || CD | Argument 1 By definition of trapezium, since ABCD is a trapezium.
| ### 3 same areas Claim 1 area(△ABC) = area(△ABD) | Argument 1 Triangles △ABC and △ABD share the same basis AB and have equal heights because of #2.
| ### 4 areas of triangles Claim 1 area(△ADE) = area(△BCE) | Argument 1 From the equal areas, see #3, of △ABC and △ABD we subtract the common area of △ABE. The remaining parts, △AED and △BCE, have the same area.

## Notes