Creating points at the intersection of lines to create Rectangles

Hello everyone.

I am trying to find intersection points of these dotted lines as shown in the picture so that I can create rectangles from that in order to find the area. I am stuck here as I am relatively new to GH. It would be great if someone can help me in addressing this problem.
(The axis has been created by pulling the points from the vertices of the rectangles onto the boundaries and then eliminating the duplicate points and connecting them both in horizontal and vertical directions)
I would be very thankful to you!