E is a midpoint of side GO, and D is a midpoint of side RO. Explain why triangle GOR has the same area as rectangle MATH.

Examine one particular solution to this investigation (if you haven’t already):
Construct segment ED. How does this segment compare with some of the other segments in the figure? Use this segment to explain why triangle GOR and rectangle MATH have the same area.

View a GSP construction of this sketch to convince yourself!