Determine if the sequence is geometric. If it is, find the common ratio, the 8th term, and the explicit formula. -2, 6, -18, 54, ...

David and alton are training for a race. they spend 35 minutes stretching and then go on a 5 mile practice run. david runs at a pace of 7 min/mile. alton runs at a pace of 8 min/mile. write an equation for each runner that shows the total length of their workout. then solve each equation showing your work