1. A 50.0 cm, uniform, 57.0 N shelf is supported horizontally by two vertical wires attached to the sloping ceiling (the figure ). A very small 26.0 N tool is placed on the shelf midway between the points where the wires are attached to it. http://session.masteringphysics.com/problemAsset/1260552/1/YF-11-23.jpg 2. All I know is that The downward force which is 83 N (26 N+ 57 N) and upward force must be equal to zero because this is an equilibrium problem. 3. I have tried to find the center of gravity: x=(m1x1+m2x2)/(m1+m2)--> 185.2040Kgcm/8.469 Kg = 21.867 cm from the left, after this I am unsure how to proceed.