I'm working on this question for a math class I'm taking. I don't think it's very hard, but for some reason I can't really get anywhere with it. Since triangle $ABC$ is 45-45-90, I called $AD$ $x$ and $BD$ $y$, then drew line segment $AE$ and tried to find the areas of the shaded regions and set them equal to each other, but I had too many variables.