PLZZZZ HELP!! SOOOO CONFUSED

Molly earns a rebate each month on her movie tickets and books. She earns $0.25 for each movie ticket and $2 for each book. Last month Molly purchased 4 movie tickets and earned $17.

Part A: Create an equation that will determine the number of books she purchased. (3 points)

Part B: Solve this equation justify