This question cannot be answered sensibly. A square yard is a measure of area, with dimensions [L2]. A linear foot is a measure of distance, with dimensions [L]. Basic dimensional analysis teaches...
My father is a carpet installer so we used this all the time. One yard = 3 feet, so an area that is 3 feet by 3 feet would equal one square yard. Since that area contains 9 square feet, then 9 sf = 1...