First, the method of square number
A figure with many squares is large, and vice versa.
Second, the overlapping method
Overlapping two graphs, it seems that which graph has a large surface area will have a large area.
Third, segmentation and replacement method.
A graphic is divided and then moved to form another graphic or similar graphic shape, and then compared.
Fourth, the spelling method (using two graphics to spell a graphic, the third graphic is larger.
Small)
Without calculating the graphic area, we can compare the areas of two graphics by the above method.