Reaching back many years in memory...
moment due to a force vector is the force magnitude (12.3 kN) times the perpendicular distance between the force vector & the point in question. Or resolve the vector into x & y components, the moments is the sum of each component times its respective x & y distance from point.
Determine the moment created about the support leg at "A" caused by the tension in the cable of 12.3kN. (see attachment for diagram)
Welcome to the PF, jmohle. On schoolwork questions, the PF rules require you to post your own attempt at a solution before we can offer tutorial help. So please write out the equations that Carl is alluding to, and see how far you can get.
