With your equations, I solved for the two unknown variables and got the correct answers for the forces. Thanks! Unfortunately, I don't really understand how you came up with those two equations in the first place. I set up a diagram and selected a pivot point force the forces, but I wasn't sure where to go from there.
Those two equations are statements that the sums of the vertical and horizontal forces on the LAMP are each zero. You don't need to worry about pivot points or moments.
