Insert
ProfilePerpendicularity
The Perpendicularity Constraint command enables you to constrain two entities in a 2D profile or a 3D profile so that they are perpendicular to each other.
You can constrain any of the following pairs of entities:
To apply the constraint, after starting the command, simply click on the two entities. The order in which you select the entities is not important. The program immediately applies the constraint and adds the identifier 
.
Note that if one of the lines is an external entity, the program may move the line in the profile so that it is perpendicular to the external entity, which remains fixed. When the perpendicular constraint it applied to two lines in a profile, the program may move one or both lines to make them perpendicular, depending on the other constraints on the profile.
