How to convert a fraction to the simplest term

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

Idon’t understand! use slope intercept form to solve: through: (2,5) slope= undefined

Typically a point in a three dimensional cartesian coordinate system is represented by which of the following answers in the picture !