One year ago, Derek joined a health club. He paid a yearly membership fee of $259.99 that covers all the clubs services expect use of the racquetball courts. Derek paid $3.75 each time he used a racquetball court. For the entire year at the health club, Derek paid a total of 436.24. Write an equation to represent the problem. Use “r” to represent the number of times Derek used one of the racquetball courts. Explain your reasoning. Solve the equation you wrote in part a to find how many times Derek used a racquetball court. Show or explain how you found your answer.