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Can somebody 1. what is the formula for finding the vertical distance between two points on a coordinate plane?

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

Which equation represents a line that passes through the point (9, -4) and has a slope of 3/5?