I'm pretty sure it would be 4 20÷5=4
When x=1 y=13 when x=3 y=19 and when x=5 y=25 you just plug the numbers in for x and solve
Step-by-step explanation:
X1 = 1
X2 = (X1) 2 - X1
X2 = 2 - 1
X2 = 1. implies that the second term of the sequence is 1.
Answer:

There are two best ways to solve this.
using cosine method:




using sine method:




There are many ways, not to make it complex, these are the best ways to solve for n. Hope it helps ~