How to turn these equations in to standers form

For the following sequence determine the common difference (if it is an arithmetic sequence) or the common ratio (if it is a geometric sequence).

Answer this question only if you know the answer! 30 points and

An architect is designing a water fountain for a park she uses the given function to model the water jet flowing from the fountain nozzles where h(x) gives the height of the water jugs in feet x feet from the starting point h(x)=-1/20x+x+15