I need to make an extension for the monitor shelf on a corner desk. I don't have a compass, but have the dimension of the new piece:
At the right angles(the back): 19.5 x 19- 1/4 x 10. The 10 " side and the 19.5 are joined by the diagonal of 23". I realize the easiest way to do this would be to have a rectangle 19.5 x 19.25, measure the 10" side, draw a line and cut, but I need to keep a finished edge on a laminate shelf board on the 23" side. Can you calculate the angles for me or give me the geometric equasion and I will figure it out myself.