1. The problem statement, all variables and given/known data Determine the product of inertia of this area with respect to the centroidal x′ and y′ axes. Locate the centroid x bar of the beam's cross-sectional area. Set a = 120mm , b = 290mm , d = 30mm , h = 390mm . 2. Relevant equations ??? 3. The attempt at a solution So I can't find anything online that would help with finding the Ix'y' value except maybe Ixy = Ix'y' + ACxCy. But I don't have anything to help find Ixy, so I'm pretty much stuck in an inertia loop. Any explanation would be great as to how the answer is -1.21e8 mm^4!