It depends on your goals.
typically it's B but it could be D
The formula to use is
n = 360/E
where
n = number of sides
E = measure of exterior angle
In our case, E = 15 so
n = 360/E
n = 360/15
n = 24
This regular polygon has 24 sides
The pattern is count by 2
Step-by-step explanation:
F(b)-F(a)/b-a
A=10 B= -2
F(a) =4 F(b)=17
17-4/-2-10
13/-12
