What are the values of a and b?

Trying to figure out the standard form equation for this graph

A33.33 percent decrease followed by a 50% increase. greater or larger that original amount?

Trang is planting shrubs beside the highway for his job. he needs to plant 500 shrubs this week. he planted 84 shrubs on monday, 92 shrubs on tuesday, 87 shrubs on wednesday, and 104 shrubs on thursday. how many shrubs does trang need to plant on friday to finish the job?