The recursive rule for a sequence is shown. an = an−1 + 9 a1 = 21 What is the explicit rule for this sequence? A) an = 12n − 9
B) an = 9n + 12
C) an = 12n + 9
D) an = 9n − 12
The difference between terms is 9
Consider "C"
a1 = 12(1) + 9 = 21
So.....this must be the correct choice
+105 
