Wash. Rev. Code § 35.27.280
A majority of the councilmembers shall constitute a quorum for the transaction of business, but a lesser number may adjourn from time to time and may compel the attendance of absent members in such manner and under such penalties as may be prescribed by ordinance.
The mayor shall preside at all meetings of the council. The mayor shall have a vote only in case of a tie in the votes of the councilmembers. In the absence of the mayor the council may appoint a president pro tempore; in the absence of the clerk, the mayor or president pro tempore, shall appoint one of the councilmembers as clerk pro tempore. The council may establish rules for the conduct of its proceedings and punish any members or other person for disorderly behavior at any meeting. At the desire of any member, the ayes and noes shall be taken on any question and entered in the journal.
RCW 35.27.280