The regulations, restrictions, boundaries and provisions of this chapter may be amended, supplemented, changed, modified or repealed as provided by law.
If a protest against any change is signed by the owners of 20% or more of the area of lots included in the proposed change or of 20% of the owners of the area of the lots adjacent thereto extending 100 feet therefrom or of 20% of the owners of the area of the lots directly opposite thereto, extended 100 feet back from the street frontage of such opposite lots, the amendment shall not become effective, except by the favorable votes of 3/4 of all the members of the Commission.
No amendment, supplement or change shall become effective until after a public hearing in relation thereto, at which hearing parties in interest and citizens shall have an opportunity to be heard. At least 15 days' notice of the time and place of such hearing shall be published in an official paper or a paper of general circulation in the City.