1. The problem statement, all variables and given/known data The figure shows the quadriceps and the patellar tendons attached to the patella (the kneecap). If the tension FT in each tendon is 1.2 kN, what is (a) the magnitude and (b) the direction of the contact force θ exerted on the patella by the femur? 2. Relevant equations FTsin θ + FTsin θ = FN (normal force) c2 = a2 + b2 - 2abcos θ 3. The attempt at a solution I've tried using the above equation and got 1.1742 kN but that is basically assuming the normal force is horizontal right and there would be no angle? I've also been playing around trying to make a triangle by moving the forces but my trig is a little rusty. I moved the lower FT up to the bottom of the top FT so that angle would be 59 degrees. Then FN would make the top of that upside down triangle. I could use the law of cosines and get 1.1818 kN. I know my sig figs aren't right but I'm just trying to show the difference. As a side note, we haven't ever used the law of cosines in class and it started out very basic and slow so I'm not sure its needed to solve this problem. I don't know how I would get the angle though.