Question: How do I make this program run

Dear,

Last week I made a question, which was kindly answered with the conclusion there might be no solutions.
Now as this cannot be (I'll explain later), I have eliminated all extra aspects of the program to just show the code where the problem is occuring. You can find it via this link prob.mw

The problem is as follows:
I have 3 points, of which I need to determine the distances from the 0,0 point. The distance between the points are known and the angle between the neutral axis and the line through a point are also known. The set-up is shown in the rough sketch. (k1,k2,k3,corner 1, corner 2, corner 3 are known; a,b,c are unknown.). With these values known, I can easily calculate a,b,c via the cosine rule.

However I want to make a sensitivity analysis for a parameter that determines the 3 corners (called f in the code). Herefore I need to become an answer of a,b,c in function of f and only f (as I need them in following calculations which are not shown in the code). However this doesnt seem to work. The program does not return a solution.

Do you guys know how I can make sure that this program is runnable, so I can get my a,b,c values in function of f? I'd be very very very thankful as I'm stuck with this crucial part of my calculation for weeks.

With kind regards
Mathieu