Point E moves from point A to point B along the AB edge (excluding points A and B).

Point F moves from point B to point C (excluding points B and C) along the BC edge.

Point G moves from point C to point D along the edge of the CD (excluding points C and D).

Point h moves from point d to point a (excluding points d and a) along the edge of DA.

They started to move at the same time, and the speed was 2 cm/s.

Set the move time to? T (seconds) (0

1. Do △HAE and △EBF have to be the same during exercise? Why? (process)

2. In the process of moving, let the area of quadrilateral EFGH be s (square centimeter), and use? t？ Algebraic time of s?

There are also some topics:/view/9c2b0a4ac850ad02de80418f.html (Baidu Library).

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