Creo™ Schematics 4.0 Help Center > Design Basics > Drawing > Construction Lines > To Delete Construction Lines
  
To Delete Construction Lines
1. To delete all construction lines, click Geometry > Delete All.
2. To delete selected construction lines, select the lines to delete, right-click choose Delete from the shortcut menu, or press DELETE.
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A single construction line that is part of a series of lines created by either offsetting or mirroring about a datum point cannot be deleted.