posted by Dawn .
Sam can do a job in X hours. Denise can do the same job in x+2 hours. How long will it take Sam and Denise to do the job together? (Express your answer in terms of x.)
Rate Sam works : ( 1 job ) / x hrs
Rate Denise works : ( 1 job ) / ( x + 2) hrs
Rate together : 1 / x + 1 / ( x + 2 ) =