How to get the intersection of a locus and a line ?

venturikites shared this question 5 months ago

I am trying to create the intersection of a locus and a line...see attached file.

Somehow it seems inpossible to do so...strange because it is however possible to put a point on a locus.

I have also tried to add the command " LocusEquation " but all I get is an error " unknown command".

There is something I am doing wrong, but I cannot figure out what.

Would you please have a look at my file and let me know how to get the intersection of the green locus and the red line ?

Thanks in advance.

Comments (3)


You get the "Unknown command" as output of a LocusEquation() command when it's not possible to determine the equation of the locus. See

For the same reason I guess that it's currently not possible to get intersections.


Anyway, in ancient times ;) Zbynek suggested a cool workaround.


I'm attaching your file where I've created the objects defined in the linked post.


A solution with Spline()

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