Answer: y = 10x
This line goes through the two points (0,0) and (1,10)
(0,0) means x = 0 and y = 0 pair up. At time x = 0 seconds, aka the starting time, the height is y = 0 (the balloon is on the ground).
(1,10) means x = 1 and y = 10 pair up. At time x = 1 second, the balloon is y = 10 feet off the ground.
