AG Mechanics CDE Practice Exam 2026 – Comprehensive Test Prep Resource

The Principal Meridians run diagonally in the rectangular survey system because these are base lines that run north and south from which the measurement lines extend east and west. This is done to accurately divide land into smaller sections for surveying and ownership determination. The other options, east and west, north and south, and vertical are incorrect as they do not represent the direction in which the Principal Meridians run.