(a) There is hereby created in each community (as herein defined) a public body corporate and politic, to be known as the "urban renewal authority" of the community: Provided, however, That such authority shall not transact any business or exercise its powers hereunder until or unless the governing body shall approve (by resolution, as herein provided) the exercise in such community of the powers, functions and duties of an authority under this article: Provided further, That, if it deems such action to be in the public interest, the governing body may, instead of such resolution, adopt a resolution approving the exercise of such powers, functions and duties by the community itself or by the housing authority, if one exists or is subsequently established in the community, and in such event, the community or housing authority, as the case may be, shall be vested with all the powers, functions, rights, duties and privileges of an urban renewal and redevelopment authority under this article.
(b) The governing body of a community shall not adopt a resolution pursuant to subsection (a) above unless it finds:
(1) That one or more slum or blighted areas (as herein defined) exist in such community, and