<h3>Derek used the racquetball courts 47 times</h3>
<em><u>Solution:</u></em>
Given that,
Derek 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
Let "r" represent the number of times Derek used one of the racquetball courts
Therefore,
Amount paid = 259.99 + 3.75r
Derek paid a total of 436.24
Therefore,
436.24 = 259.99 + 3.75r
3.75r = 436.24 - 259.99
3.75r = 176.25
Divide both sides by 3.75
r = 47
Thus Derek used the racquetball courts 47 times