how to split two lines of different shape files at their point of intersection in arcgis 9.x.the manual split is not giving a good split point as snapping is not that good in 9.3, even after tolerance.
There are two options:
A. Split Line at Point method
Analysis Tools > Overlay > Intersect toolto find the points where the lines intersect and generate a feature class of type Point. That is, the tool’s Output Type field is set to Point.
Use the output points in
Data Management Tools > Features > Split Line at Point toolto break apart the lines at the point locations (this tool requires an Advanced license).
B. Use QGIS Split Lines with Lines Tool (in case you don't have Advanced ArcGIS License)
Processing -> QGIS Algorithms -> Vector Overlay Tools -> Split Lines with Lines. Then you need to define the input line shapefile and the intersect line shapefile.