Danny and josh are going to paint josh's neighbor's fence. josh painted the fence by himself two years ago. four years ago, danny painted the same fence and did it 9 hours faster than josh. together, danny and josh finished painting the fence in just 7 hours. write the work equation that will represent this situation. solve the equation to find how long it would take danny and josh to paint the fence if each was doing it by himself. be sure to explain each step. did you have to find the least common denominator? why is a least common denominator important for solving rational polynomial equations?