Arc tracing problem

I am trying to trace a curved area of an inserted image,using the 3 point arc command.

When I try to insert the 2nd point of the arc,a dotted line appears with an extension statement and a marker,which overrides my selection,why does this occur and how do I get rid of it.??

Can you show us what you are experiencing?

If you snap to the end points of the arc, you can then grip stretch the mid point grip of the arc to the line which you are tracing, with the perpendicular snap.

Can you show us what you are experiencing?

This is a screen dump showing the problem.

I have selected a point on the image and the screen shows the resultant location of the point.Trying to compensate won't work,as the revised location varies?

Doc1.docx

Not sure what the problem is. You've put in two points, you only have to give it the third point to get your arc. The dotted line tells you where the arc might go based on the two points you've already given.

If that's not the real problem, you may be having trouble because the entity you're tracing isn't an arc but a spiral, that is, the angle changes along its length.

Not sure what the problem is. You've put in two points, you only have to give it the third point to get your arc. The dotted line tells you where the arc might go based on the two points you've already given.

 

If that's not the real problem, you may be having trouble because the entity you're tracing isn't an arc but a spiral, that is, the angle changes along its length.

I have picked only the 1st point of the 3,I am being driven,for some reason,to the 2nd point-------!!!!!!

Have you tried continuing through with your selections?

Can you post the .dwg?