1. The problem statement, all variables and given/known data Calculate the reaction force at A? 2. Relevant equations ΣMb = 0 3. The attempt at a solution As there is a pin joint at B it is possible to consider the bar only from A-B. From here I applied ΣMb = 0 120 + 20*2 + Ay*4 = 0 This gives Ay = -40kn Also since there are no forces in the x direction Ax = 0 and Hence A = -40kn or 40n downwards However this is wrong. I am not sure what I am doing wrong unless it is something that the sum of the y forces don't equal 0, but I think there would be a force at By= 60kn up to combat this. Any help would be appreciated, thanks.