(a) The district may annex one or more tracts of territory in accordance with the method provided by this subchapter.
(b) A registered voter who resides in a defined territory may file a petition with the board requesting inclusion of the territory in the district. The territory:
(1) must be contiguous to the district’s boundaries or to territory to be annexed under this subchapter; and
(2) may not be located in the boundaries of another district or a district for which the legislature has enacted enabling legislation.

(c) The petition must:
(1) describe the territory to be annexed; and
(2) be signed by the lesser of:
(A) at least 100 registered voters who reside in that territory; or
(B) a majority of the registered voters.
(d) The board may act simultaneously on several petitions for annexation. If more than one petition requests annexation of the same territory, the board must act on the first petition filed.
(e) The board may not amend a petition.