Algebra 2 (1st Edition)

As we can see, $a_1=5$ and each term is $\frac{3}{4}$ ($\frac{17}{4}-2=\frac{7}{2}--\frac{17}{4}=-\frac{3}{4}$) less than the previous one, so $a_n=a_{n-1}-\frac{3}{4}$ is the recursive rule (with $a_1=5$).