|Sketch → Sketcher constraints → Constrain parallel|
|Constraint Vertical, Constraint Horizontal|
The Constrain Parallel constraint forces two selected straight lines or edges to be parallel to each other.
The sketch contains two randomly oriented lines.
Select both lines by clicking successively on each of them.
Apply the Constrain Parallel constraint by selecting the Constrain Parallel icon from the Sketcher constraints toolbar or by selecting the Constraint Parallel menu item from the Sketcher constraints sub menu of the Sketcher (Sketcher workbench selected) or Part Design (Part Design workbench selected) menu item.
The selected lines are forced to be parallel to each other. Changing the orientation of one line will change the orientation of the other to be the same.