A hearing described in this chapter may be held only after giving public notice. However, public notice of regularly scheduled meetings of a council is not required. A hearing may be adjourned from time to time until the board or council makes findings by resolution as to the expedience of the matter being considered. Where this chapter requires written personal notice of a hearing, notice may be given by deposit in the United States mail, first class postage prepaid, no later than the eighth day before the date of the hearing.