Fillet arc and line, automatically extend/cut arc

Geometry
1

Hi All,

I’m using Arc.ByFillet between and arc and a line. See the result below in 2 different cases and different radius

is there a way to automatically cut/extend the initial arc 1. I need to be able to specify the radius of the fillet.

Thanks

image
image.jpg1195×714 60.2 KB

image
image.jpg1054×713 54.6 KB