Use the alignment tools to adjust the relative position of a graphic object compared to another object. Clicking on the Alignment icon in the Drawing toolbar opens the extended toolbar. The same alignment options are available from the right-click menu.
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The Align extended toolbar.
The toolbar has six icons. The first three determine the horizontal alignment of the selected objects (Left, Center, Right); the other three determine the vertical alignment of the selected objects (Top, Middle, Bottom). If only one object is selected, it is aligned to the page, however when in a group, a single object is aligned to the edge of the group selection.