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近几年来有关矩形的中考题频繁出现,问题情景也在不断创新,其中折叠、旋转是矩形问题的主旋律,发现、探索是考查的着力点.下面以几道2005年中考题为例加以说明. 亮点之一:折叠问题例1 (荆州)如图1所示,将矩形纸片ABCD沿虚线EF折叠,使点A落在点G上,点D落在点H上;然后再沿虚线GH折叠,使点B落在点E上.点C落在点F上.折叠完后,剪一个直径在BC上的半圆,再展开,则展开后的图形为( ).
In recent years, the questions about rectangles have appeared frequently, and the problem scenarios have also been constantly innovating. Among them, folding and rotation are the main melody of the rectangle problem, and discovery and exploration are the focus of examination. The following uses several 2005 mid-term exam questions as examples. One of the highlights: Folding Problem Example 1 (Jingzhou) As shown in Figure 1, the rectangular paper ABCD is folded along the dotted line EF so that the point A falls on the point G and the point D falls on the point H; then it is folded along the dotted line GH. Let point B fall on point E. Point C falls on point F. After folding, cut a semicircle whose diameter is on BC, and then expand, the expanded figure is ().