1. The problem statement, all variables and given/known data If F_1 = 100N , F_2 = 120N and F_3 = 80N , determine the magnitude and coordinate direction angles of the resultant couple moment. 2. Relevant equations M=Fd M=r x F MR=Ʃ(r x F) 3. The attempt at a solution I found the couple moment for each force: M1=F1d=100(0.2) or (-20j using right hand rule) M2=F2d=120(0.2) or +24i M3=F3d=80(0.2) or -16k M4=this is what im having problems with...not sure how to get the moment for F4... if do 150(.3)(cos30)=38.97 i get the wrong resultant. The correct answer should be (MC)R=71.9 Nm... Any help would be greatly appreciated.