You can calculate the difference/vector of both points:

then calculate the magnitude/length like pythagoras
Step-by-step explanation:
a(n) = a +(n-1)d
d=1/4 -1/2 =-1/4
°.° a(15) = 1/2 +(15–1) -1/4
a(15) = 1/2 -3.5
=<u>-3</u>
<u>hope it will help</u>
Answer:
1. 2 and 2 is c
Step-by-step explanation: