Use this procedure to extend fixed straights to an intersection point.
Note: You can only perform this procedure when the alignment displays implied intersection points of two fixed straights that are joined by a free curve or curve group.
- Select the alignment.
A
grip is displayed at the implied intersection point. 
- Hover the cursor over the grip.
- From the grip menu, select Solve IP.
The straights extend to the intersection point, which now displays a 
grip. 
grip.