Is the relationship shown by the data linear? x -9, -5, -1, 3 y -2,-7,-12, -17

                x               y
                     
              -9              -2
             -5               -7
             -1              -12
              3               -17

ur x's all have a difference of 4, and ur y's all have a difference of -5...so yes, this is linear with a slope of (-7+2) / (-5 + 9) = -5/4

The answer would be 13.5 minutes.