In exercising the above-mentioned powers, the Board of Adjustment may, in conformity with the provisions of this chapter, reverse or affirm, wholly or partly, or modify the order, requirement, decision or determination appealed from and may make such order, requirement, decision or determination as ought to be made, and to that end shall have all the powers of the officer from whom the appeal is taken. The concurring vote of at least three members of the Board of Adjustment shall be necessary to reverse any order, requirement and decision or determination of any such administrative officer, or to decide in favor of the applicant, or to decide any matter upon which it is required to pass under this chapter or to effect any variation in such chapter.