Align:

1. (Optional) Under Modify and Surface Mode, select a plane which you would like the edge to fix in and press Space to lock it.
2. Under Modify and Vertex Mode, select (or Hold Ctrl to multiply select the lines) you want to align with.
3. Click Align or press Shift to change to Align mode, and click the Target edge.
4. The edges you selected on Step 2 will be aligned with the Target you selected on Step 3 and fixed in the plane you selected on Step 1.