A simple way to do this is to draw two lines, one 10 m long and the other 5 m long off the end of the first line. You can fix the start node of the 10 m long line. There are many ways to connect the two lines together. Use Shared Topology in DesignModeler or SpaceClaim. Or do a Mesh Merge in Mechanical.

In step 1, apply the displacement to the node at the 10 m vertex. The 5 m long extension will remain straight. Then you can do what you want in step 2.