On 5/4/2011 5:16 AM, Chris Holford wrote:
In , Tim Wescott
writes
Consider two circles, of arbitrary diameter, and a point, all on a plane.

I want to inscribe an arc that is tangent to both circles, and which
passes through the point.

Anyone know a way to construct the arc? I'm not snickering in the
background here as I pose puzzles -- this is a drafting problem that I'm
running into quite a lot lately.

Just tried it using an ancient version of EasyCad. I just drew 3 circles
and used the "draw circle tangent to 3 circles" instruction, and then
trimmed the new circle to get the required arc.

The third circle can be made very very small so that in practical terms
it approximates to a point.

In autocad you can draw a circle tan, tan ,tan to the two circles and
the point