Hi luis, thanks for posting the example file, that helps a lot to clarify!
From what I understand of what you are looking for, you could possibly use Scale 1D instead of control point editing to get the right result.
So for example select the orange curve, and then run the Transform > Scale > Scale 1D command.
For the origin of the scale pick this point here (where the mouse cursor is at):
For the direction and first reference point for the scale, pick the intersection point that is on the orange curve, here:
Now for the final stage of Scale1D you have the option to either enter a scale factor like 2.0 to double the size, or you can pick another reference point which will calculate the scale factor for you to exactly scale from the first reference point to the second one.
So for your case here you would pick the ending point you want here:
And then that stretches that curve by exactly the amount needed to relocate from the first intersection to the second intersection:
So if you want to do a kind of a stretching from one particular point exactly to match another one, Scale1D can be useful for that instead of doing any point manipulation stuff.
 Michael
