Plateax or Plateaux: How To spell?

The word Plateax is misspelled against Plateaux, which is plural of "Plateau"

Word contains consecutive vowels 'AU' in between alphabets plate & x is misspelled as 'A' as letter 'U' is phonetically ignored
Wrong Spelling: plate-a-x
Correct Spelling: plate-au-x
Explore spell check of Plateaux to spell without errors.