Answer: The plateau slopes to west towards Gulf of California * Pacific Ocean
Explanation: To the north is Chihuahua desert & Sonoran desert to its west, both stretching across USA border. To east of Mexican Plateau along the coast of Gulf of Mexico is Sierra Madre del Orientale. To its west is Sierra Madre del Occidental (running through Central Mexico), both merging to Sierra Madre del Sur to south, at the beginning of which is located Mexico City at an altitude more than a mile high from MSL.