Question

The nth term of an ap is 15-17n . find it's common difference
* WRONG ANSWERS WILL BE REPORTED

Answer 1

U can find Its first term by putting n= 1
i.e. 
15-7=8 
2nd term =15-14=1

Hence Common difference is 2nd term-1st term 
1-8=> -7


Got ittt

Answer 2

a(n)=15-17n
a(1)=15-17=-2
a(2)=15-34=-19
a(3)=15-51=-36
d=a(2)-a(1)=-19-(-2)=-19+2=-17
=a(3)-a(2)=-36-(-19)=-36+19=-17
d=-17