I'm trying to divide a circle that's 32" in diameter into nine sections using 3/4" thick cross-lapped rails that divide it up. Here's the picture:

My objective is to join the rails so that the nine partitioned areas are as close to being equal as possible. Two pairs of four areas (1) and (2) are identical, and the center (3) should be a square.

It's impossible to make the areas of all nine sections equal, but what should the dimension X be so that all nine sections are as close to each other in size as possible? (i.e., minimize the deviation between them)