Do you remember a problem that consisted of three squares or rectangles that was solved by three equations in three unknowns? I lost the original after I had made certain simplifications to create a 3-D model of the solution. I’d like to find the original post. The equations were (roughly) x+y+z=87 -x+y=33 y-z=11. Thanks if you know where I can find it. My model is pictured.
3D Lol