A rectangle has a length of 12 yards less than 8 times its width. If the area of the rectangle is 4320 square yards, find the length of the rectangle.

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