Which expressions apply to 15x+39?

What is the percent of increase for a population that changed from 438,000 to 561,000

You are assembling pieces of an iron gate to complete a fence. the finished gate will look like the one below. in order to assemble the gate it is important to under how the pieces are related. part 1: how are pies 1 and 2 in the archway related? part 2: how are the rectangular sections 5 and 6 in the center of the gate related to each other?

Answer these questions showing your work plz