6x + 6y = 0 -10x + 4y = 28​

Answer these questions showing your work plz

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

How do i do this activity, is appreciated