The variables a, b, and c represent polynomials where a = x + 1, b = x2 + 2x − 1, and c = 2x. what is ab + c in simplest form? x3 + 3x − 1 x3 + 4x − 1 x3 + 3x2 + 3x − 1 x3 + 2x2 − x + 1

Randy and trey take turns cleaning offices on the weekends. it takes randy at most 4 hours to clean the offices. it takes trey at most 6 hours to clean the offices. what is the greatest amount of time it would take them to clean the offices together? 2.4 hours 2.5 hours