An elevator went from the bottom to the top of a 240m tower and remained there for 12 seconds and returned to the bottom in an elapsed time of 2 minutes. if the elevator traveled 1m/s faster on the way down, find speed going up

How can you construct perpendicular lines and prove theorems about perpendicular lines

Donald has x twenty-dollar bills and 11 ten-dollar bill. how much money does donald have? write your answer as an expression.

Dean and karlene get paid to write songs. dean is paid a one-time fee of $20 plus $80 per day. karlene is paid a one-time fee of $25 plus $100 per day. write an expression to represent how much a producer will pay to hire both to work the same number of days on a song.