Select Dimension
in the Annotations toolbar (Dimensions sub-toolbar).
Select both lines to be dimensioned, one after the other.
The angle dimension appears in the sector associated
to both selected lines.
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Drag the angle dimension line to the desired quadrant
(or sector).
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To move the dimension to a new sector, perform either
of the following:
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Click anywhere to create the angle dimension.
Select Angle Dimensions
in the Annotations toolbar.
Select two lines in the rectangle to create an angle
dimension.
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Click to create the angle dimension, then right-click
the dimension and select Half Dimension.
Click in a free space to create the dimension.
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Note:
The half angle dimension's orientation depends
on the order in which you select the lines to be dimensioned. If you
need to modify the dimension, use
Re-routing Dimensions
.