When measuring the distance between two features, you have the option of determining how the distance is to be measured by using these orientation options in the Distance dialog box (Insert | Dimension | Distance).
Measure the distance between the first selected feature parallel or perpendicular to either the second or another selected feature.
Measure the distance between the first selected feature and the second selected feature parallel to or perpendicular to a specific axis.
The Perpendicular To and the Parallel To options enable you to determine the orientation of the features.
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