(a) Before the establishment or change of building or set-back lines, the commissioners court must hold at least one public hearing on the establishment or change. The court shall publish notice of the time and place of the hearing in a newspaper of general circulation in the county before the 15th day before the date of the hearing. The court may adjourn the hearing from time to time.
(b) The commissioners court may establish or change a building or set-back line only by an order passed by at least a majority vote of the full membership of the court.