The mayor shall be elected in the manner provided by article III of this Charter to serve for a term of four (4) years, or until his or her successor is elected and qualified. The mayor shall be the official head of the city government and shall preside at all meetings of the city council. The mayor shall have the right to vote only when there are an equal number of votes in the affirmative and the negative on any motion before the council. The mayor shall exercise such powers and perform such duties as presently are or hereafter may be conferred by the General Statutes of North Carolina, by this Charter, and by the ordinances of the city.