To Divide Entities
You can divide a section entity into two or more new entities. If the entity is dimensioned, delete the dimension before using the Divide command.
1. Click Sketch > Divide.
2. Click the entity at the locations where you want to divide. The entity is divided at the specified location.
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To create a divide at an intersection, click near the intersection. The curser automatically snaps to the intersection and the divide is created.