Write the recursive formula for the geometric sequence.

a1 = -2 a2 = 8 a3 = -32

a. an = -4 an-1

b. an = -2 an-1

c. an = -2 • an-1

d. an = -4 • an-1

Sophia wrote an equation to represent the revenue of a movie theater for one day. she let x represent the number of child tickets sold and y represents the nunver of adult tickets sold. if a child ticket cost $4, an adult ticket cost $6, and the total revenue for the daybwas $420, which equation could sophia use to represent the number of chikd and adult tickets that were sold?