Assignment:
Last year Otto's garden was square. This year he plans to make it smaller by shortening one side 5 feet and the other 8 feet. If the area of the smaller garden will be 180 square feet, then what was the size of Otto's garden last year 80 square feet, then what was the size of Otto's garden last year?
Provide complete and step by step solution for the question and show calculations and use formulas.