This feature is enabled when you select a simple object. You can change the shape of simple graphic objects such as line, rectangle, arc, circular sector, chord, polyline, and polygon. When you select an object, the 
icon is enabled, and you can change the shape of the object by dragging its handles.
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b) You can change the shape of the object by dragging its handles. The top-right handle was dragged in this example.
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